Recommended settings for EOP and Microsoft Defender for Office 365 security
Tip
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Applies to
- Exchange Online Protection
- Microsoft Defender for Office 365 plan 1 and plan 2
- Microsoft 365 Defender
Exchange Online Protection (EOP) is the core of security for Microsoft 365 subscriptions and helps keep malicious emails from reaching your employee's inboxes. But with new, more sophisticated attacks emerging every day, improved protections are often required. Microsoft Defender for Office 365 Plan 1 or Plan 2 contain additional features that give admins more layers of security, control, and investigation.
Although we empower security administrators to customize their security settings, there are two security levels in EOP and Microsoft Defender for Office 365 that we recommend: Standard and Strict. Although customer environments and needs are different, these levels of filtering will help prevent unwanted mail from reaching your employees' Inbox in most situations.
To automatically apply the Standard or Strict settings to users, see Preset security policies in EOP and Microsoft Defender for Office 365.
This article describes the default settings, and also the recommended Standard and Strict settings to help protect your users. The tables contain the settings in the Microsoft 365 Defender portal and PowerShell (Exchange Online PowerShell or standalone Exchange Online Protection PowerShell for organizations without Exchange Online mailboxes).
Note
The Office 365 Advanced Threat Protection Recommended Configuration Analyzer (ORCA) module for PowerShell can help you (admins) find the current values of these settings. Specifically, the Get-ORCAReport cmdlet generates an assessment of anti-spam, anti-phishing, and other message hygiene settings. You can download the ORCA module at https://www.powershellgallery.com/packages/ORCA/.
In Microsoft 365 organizations, we recommend that you leave the Junk Email Filter in Outlook set to No automatic filtering to prevent unnecessary conflicts (both positive and negative) with the spam filtering verdicts from EOP. For more information, see the following articles:
Anti-spam, anti-malware, and anti-phishing protection in EOP
Anti-spam, anti-malware, and anti-phishing are EOP features that can be configured by admins. We recommend the following Standard or Strict configurations.
EOP anti-spam policy settings
To create and configure anti-spam policies, see Configure anti-spam policies in EOP.
Security feature name | Default | Standard | Strict | Comment |
---|---|---|---|---|
Bulk email threshold & spam properties | ||||
Bulk email threshold BulkThreshold |
7 | 6 | 5 | For details, see Bulk complaint level (BCL) in EOP. |
MarkAsSpamBulkMail | On |
On |
On |
This setting is only available in PowerShell. |
Increase spam score settings | Off | Off | Off | All of these settings are part of the Advanced Spam Filter (ASF). For more information, see the ASF settings in anti-spam policies section in this article. |
Mark as spam settings | Off | Off | Off | Most of these settings are part of ASF. For more information, see the ASF settings in anti-spam policies section in this article. |
Contains specific languages EnableLanguageBlockList LanguageBlockList |
Off $false Blank |
Off $false Blank |
Off $false Blank |
We have no specific recommendation for this setting. You can block messages in specific languages based on your business needs. |
From these countries EnableRegionBlockList RegionBlockList |
Off $false Blank |
Off $false Blank |
Off $false Blank |
We have no specific recommendation for this setting. You can block messages from specific countries based on your business needs. |
Test mode (TestModeAction) | None | None | None | This setting is part of ASF. For more information, see the ASF settings in anti-spam policies section in this article. |
Actions | Wherever you select Quarantine message, a Select quarantine policy box is available. Quarantine policies define what users are allowed to do to quarantined messages. Standard and Strict preset security policies use the default quarantine policies (AdminOnlyAccessPolicy or DefaultFullAccessPolicy with no quarantine notifications) as described in the table here. When you create a new anti-spam policy, a blank value means the default quarantine policy is used to define the historical capabilities for messages that were quarantined by that particular verdict (AdminOnlyAccessPolicy with no quarantine notifications for High confidence phishing; DefaultFullAccessPolicy with no quarantine notifications for everything else). Admins can create and select custom quarantine policies that define more restrictive or less restrictive capabilities for users in the default or custom anti-spam policies. For more information, see Quarantine policies. |
|||
Spam detection action SpamAction |
Move message to Junk Email folder MoveToJmf |
Move message to Junk Email folder MoveToJmf |
Quarantine message Quarantine |
|
High confidence spam detection action HighConfidenceSpamAction |
Move message to Junk Email folder MoveToJmf |
Quarantine message Quarantine |
Quarantine message Quarantine |
|
Phishing detection action PhishSpamAction |
Move message to Junk Email folder* MoveToJmf |
Quarantine message Quarantine |
Quarantine message Quarantine |
* The default value is Move message to Junk Email folder in the default anti-spam policy and in new anti-spam policies that you create in PowerShell. The default value is Quarantine message in new anti-spam policies that you create in the Microsoft 365 Defender portal. |
High confidence phishing detection action HighConfidencePhishAction |
Quarantine message Quarantine |
Quarantine message Quarantine |
Quarantine message Quarantine |
|
Bulk detection action BulkSpamAction |
Move message to Junk Email folder MoveToJmf |
Move message to Junk Email folder MoveToJmf |
Quarantine message Quarantine |
|
Retain spam in quarantine for this many days QuarantineRetentionPeriod |
15 days | 30 days | 30 days | This value also affects messages that are quarantined by anti-phishing policies. For more information, see Quarantined email messages in EOP. |
Enable spam safety tips InlineSafetyTipsEnabled |
Selected $true |
Selected $true |
Selected $true |
|
Enable zero-hour auto purge (ZAP) for phishing messages PhishZapEnabled |
Selected $true |
Selected $true |
Selected $true |
|
Enable ZAP for spam messages SpamZapEnabled |
Selected $true |
Selected $true |
Selected $true |
|
Allow & block list | ||||
Allowed senders AllowedSenders |
None | None | None | |
Allowed sender domains AllowedSenderDomains |
None | None | None | Adding domains to the allowed senders list is a very bad idea. Attackers would be able to send you email that would otherwise be filtered out. Use the spoof intelligence insight and the Tenant Allow/Block List to review all senders who are spoofing sender email addresses in your organization's email domains or spoofing sender email addresses in external domains. |
Blocked senders BlockedSenders |
None | None | None | |
Blocked sender domains BlockedSenderDomains |
None | None | None |
ASF settings in anti-spam policies
For more information about Advanced Spam Filter (ASF) settings in anti-spam policies, see Advanced Spam Filter (ASF) settings in EOP.
Security feature name | Default | Recommended Standard |
Recommended Strict |
Comment |
---|---|---|---|---|
Image links to remote sites IncreaseScoreWithImageLinks |
Off | Off | Off | |
Numeric IP address in URL IncreaseScoreWithNumericIps |
Off | Off | Off | |
URL redirect to other port IncreaseScoreWithRedirectToOtherPort |
Off | Off | Off | |
Links to .biz or .info websites IncreaseScoreWithBizOrInfoUrls |
Off | Off | Off | |
Empty messages MarkAsSpamEmptyMessages |
Off | Off | Off | |
Embed tags in HTML MarkAsSpamEmbedTagsInHtml |
Off | Off | Off | |
JavaScript or VBScript in HTML MarkAsSpamJavaScriptInHtml |
Off | Off | Off | |
Form tags in HTML MarkAsSpamFormTagsInHtml |
Off | Off | Off | |
Frame or iframe tags in HTML MarkAsSpamFramesInHtml |
Off | Off | Off | |
Web bugs in HTML MarkAsSpamWebBugsInHtml |
Off | Off | Off | |
Object tags in HTML MarkAsSpamObjectTagsInHtml |
Off | Off | Off | |
Sensitive words MarkAsSpamSensitiveWordList |
Off | Off | Off | |
SPF record: hard fail MarkAsSpamSpfRecordHardFail |
Off | Off | Off | |
Sender ID filtering hard fail MarkAsSpamFromAddressAuthFail |
Off | Off | Off | |
Backscatter MarkAsSpamNdrBackscatter |
Off | Off | Off | |
Test mode TestModeAction) |
None | None | None | For ASF settings that support Test as an action, you can configure the test mode action to None, Add default X-Header text, or Send Bcc message (None , AddXHeader , or BccMessage ). For more information, see Enable, disable, or test ASF settings. |
EOP outbound spam policy settings
To create and configure outbound spam policies, see Configure outbound spam filtering in EOP.
For more information about the default sending limits in the service, see Sending limits.
Note
Outbound spam policies are not part of Standard or Strict preset security policies. The Standard and Strict values indicate our recommended values in the default outbound spam policy or custom outbound spam policies that you create.
Security feature name | Default | Recommended Standard |
Recommended Strict |
Comment |
---|---|---|---|---|
Set an external message limit RecipientLimitExternalPerHour |
0 | 500 | 400 | The default value 0 means use the service defaults. |
Set an internal message limit RecipientLimitInternalPerHour |
0 | 1000 | 800 | The default value 0 means use the service defaults. |
Set a daily message limit RecipientLimitPerDay |
0 | 1000 | 800 | The default value 0 means use the service defaults. |
Restriction placed on users who reach the message limit ActionWhenThresholdReached |
Restrict the user from sending mail until the following day BlockUserForToday |
Restrict the user from sending mail BlockUser |
Restrict the user from sending mail BlockUser |
|
Automatic forwarding rules AutoForwardingMode |
Automatic - System-controlled Automatic |
Automatic - System-controlled Automatic |
Automatic - System-controlled Automatic |
|
Send a copy of outbound messages that exceed these limits to these users and groups BccSuspiciousOutboundMail BccSuspiciousOutboundAdditionalRecipients |
Not selected $false Blank |
Not selected $false Blank |
Not selected $false Blank |
We have no specific recommendation for this setting. This setting only works in the default outbound spam policy. It doesn't work in custom outbound spam policies that you create. |
Notify these users and groups if a sender is blocked due to sending outbound spam NotifyOutboundSpam NotifyOutboundSpamRecipients |
Not selected $false Blank |
Not selected $false Blank |
Not selected $false Blank |
The default alert policy named User restricted from sending email already sends email notifications to members of the TenantAdmins (Global admins) group when users are blocked due to exceeding the limits in policy. We strongly recommend that you use the alert policy rather than this setting in the outbound spam policy to notify admins and other users. For instructions, see Verify the alert settings for restricted users. |
EOP anti-malware policy settings
To create and configure anti-malware policies, see Configure anti-malware policies in EOP.
Security feature name | Default | Standard | Strict | Comment |
---|---|---|---|---|
Protection settings | ||||
Enable the common attachments filter EnableFileFilter |
Selected $true |
Selected $true |
Selected $true |
This setting quarantines messages that contain attachments based on file type, regardless of the attachment content. For the list of file types, see Anti-malware policies. |
Common attachment filter notifications (When these file types are found) FileTypeAction |
Quarantine the message Quarantine |
Quarantine the message Quarantine |
Quarantine the message Quarantine |
|
Enable zero-hour auto purge for malware ZapEnabled |
Selected $true |
Selected $true |
Selected $true |
|
Quarantine policy | AdminOnlyAccessPolicy | AdminOnlyAccessPolicy | AdminOnlyAccessPolicy | When you create a new anti-malware policy, a blank value means the default quarantine policy is used to define the historical capabilities for messages that were quarantined as malware (AdminOnlyAccessPolicy with no quarantine notifications). Standard and Strict preset security policies use the default quarantine policy (AdminOnlyAccessPolicy with no quarantine notifications) as described in the table here. Admins can create and select custom quarantine policies that define more capabilities for users in the default or custom anti-malware policies. For more information, see Quarantine policies. |
Admin notifications | ||||
Notify an admin about undelivered messages from internal senders EnableInternalSenderAdminNotifications InternalSenderAdminAddress |
Not selected $false |
Not selected $false |
Not selected $false |
We have no specific recommendation for this setting. |
Notify an admin about undelivered messages from external senders EnableExternalSenderAdminNotifications ExternalSenderAdminAddress |
Not selected $false |
Not selected $false |
Not selected $false |
We have no specific recommendation for this setting. |
Customize notifications | We have no specific recommendations for these settings. | |||
Use customized notification text CustomNotifications |
Not selected $false |
Not selected $false |
Not selected $false |
|
From name CustomFromName |
Blank $null |
Blank $null |
Blank $null |
|
From address CustomFromAddress |
Blank $null |
Blank $null |
Blank $null |
|
Customize notifications for messages from internal senders | These settings are used only if Notify an admin about undelivered messages from internal senders is selected. | |||
Subject CustomInternalSubject |
Blank $null |
Blank $null |
Blank $null |
|
Message CustomInternalBody |
Blank $null |
Blank $null |
Blank $null |
|
Customize notifications for messages from external senders | These settings are used only if Notify an admin about undelivered messages from external senders is selected. | |||
Subject CustomExternalSubject |
Blank $null |
Blank $null |
Blank $null |
|
Message CustomExternalBody |
Blank $null |
Blank $null |
Blank $null |
EOP anti-phishing policy settings
For more information about these settings, see Spoof settings. To configure these settings, see Configure anti-phishing policies in EOP.
The spoof settings are inter-related, but the Show first contact safety tip setting has no dependency on spoof settings.
Security feature name | Default | Standard | Strict | Comment |
---|---|---|---|---|
Phishing threshold & protection | ||||
Enable spoof intelligence EnableSpoofIntelligence |
Selected $true |
Selected $true |
Selected $true |
|
Actions | ||||
If message is detected as spoof AuthenticationFailAction |
Move message to the recipients' Junk Email folders MoveToJmf |
Move message to the recipients' Junk Email folders MoveToJmf |
Quarantine the message Quarantine |
This setting applies to spoofed senders that were automatically blocked as shown in the spoof intelligence insight or manually blocked in the Tenant Allow/Block List. If you select Quarantine the message, an Apply quarantine policy box is available to select the quarantine policy that defines what users are allowed to do to messages that are quarantined as spoofing. When you create a new anti-phishing policy, a blank value means the default quarantine policy is used to define the historical capabilities for messages that were quarantined as spoofing (DefaultFullAccessPolicy with no quarantine notifications). Standard and Strict preset security policies use the default quarantine policy (DefaultFullAccessPolicy with no quarantine notifications) as described in the table here. Admins can create and select custom quarantine policies that define more restrictive or less restrictive capabilities for users in the default or custom anti-phishing policies. For more information, see Quarantine policies. |
Show first contact safety tip EnableFirstContactSafetyTips |
Not selected $false |
Not selected $false |
Not selected $false |
For more information, see First contact safety tip. |
Show (?) for unauthenticated senders for spoof EnableUnauthenticatedSender |
Selected $true |
Selected $true |
Selected $true |
Adds a question mark (?) to the sender's photo in Outlook for unidentified spoofed senders. For more information, see Unauthenticated sender indicators. |
Show "via" tag EnableViaTag |
Selected $true |
Selected $true |
Selected $true |
Adds a via tag (chris@contoso.com via fabrikam.com) to the From address if it's different from the domain in the DKIM signature or the MAIL FROM address. For more information, see Unauthenticated sender indicators. |
Microsoft Defender for Office 365 security
Additional security benefits come with a Microsoft Defender for Office 365 subscription. For the latest news and information, you can see What's new in Defender for Office 365.
Important
The default anti-phishing policy in Microsoft Defender for Office 365 provides spoof protection and mailbox intelligence for all recipients. However, the other available impersonation protection features and advanced settings are not configured or enabled in the default policy. To enable all protection features, modify the default anti-phishing policy or create additional anti-phishing policies.
Although there's no default Safe Attachments policy or Safe Links policy, the Built-in protection preset security policy provides Safe Attachments protection and Safe Links protection to all recipients (users who aren't defined in the Standard or Strict preset security policies or in custom Safe Attachments policies or Safe Links policies). For more information, see Preset security policies in EOP and Microsoft Defender for Office 365.
Safe Attachments for SharePoint, OneDrive, and Microsoft Teams protection and Safe Documents protection have no dependencies on Safe Links policies.
If your subscription includes Microsoft Defender for Office 365 or if you've purchased Defender for Office 365 as an add-on, set the following Standard or Strict configurations.
Anti-phishing policy settings in Microsoft Defender for Office 365
EOP customers get basic anti-phishing as previously described, but Defender for Office 365 includes more features and control to help prevent, detect, and remediate against attacks. To create and configure these policies, see Configure anti-phishing policies in Defender for Office 365.
Advanced settings in anti-phishing policies in Microsoft Defender for Office 365
For more information about this setting, see Advanced phishing thresholds in anti-phishing policies in Microsoft Defender for Office 365. To configure this setting, see Configure anti-phishing policies in Defender for Office 365.
Security feature name | Default | Standard | Strict | Comment |
---|---|---|---|---|
Phishing email threshold PhishThresholdLevel |
1 - Standard 1 |
3 - More aggressive 3 |
4 - Most aggressive 4 |
Impersonation settings in anti-phishing policies in Microsoft Defender for Office 365
For more information about these settings, see Impersonation settings in anti-phishing policies in Microsoft Defender for Office 365. To configure these settings, see Configure anti-phishing policies in Defender for Office 365.
Security feature name | Default | Standard | Strict | Comment |
---|---|---|---|---|
Phishing threshold & protection | ||||
Enable users to protect (impersonated user protection) EnableTargetedUserProtection TargetedUsersToProtect |
Not selected $false none |
Selected $true <list of users> |
Selected $true <list of users> |
We recommend adding users (message senders) in key roles. Internally, protected senders might be your CEO, CFO, and other senior leaders. Externally, protected senders could include council members or your board of directors. |
Enable domains to protect (impersonated domain protection) | Not selected | Selected | Selected | |
Include domains I own EnableOrganizationDomainsProtection |
Off $false |
Selected $true |
Selected $true |
|
Include custom domains EnableTargetedDomainsProtection TargetedDomainsToProtect |
Off $false none |
Selected $true <list of domains> |
Selected $true <list of domains> |
We recommend adding domains (sender domains) that you don't own, but you frequently interact with. |
Add trusted senders and domains ExcludedSenders ExcludedDomains |
None | None | None | Depending on your organization, we recommend adding senders or domains that are incorrectly identified as impersonation attempts. |
Enable mailbox intelligence EnableMailboxIntelligence |
Selected $true |
Selected $true |
Selected $true |
|
Enable intelligence for impersonation protection EnableMailboxIntelligenceProtection |
Off $false |
Selected $true |
Selected $true |
This setting allows the specified action for impersonation detections by mailbox intelligence. |
Actions | Wherever you select Quarantine the message, a Select quarantine policy box is available. Quarantine policies define what users are allowed to do to quarantined messages. Standard and Strict preset security policies use the default quarantine policy (DefaultFullAccessPolicy with no quarantine notifications) as described in the table here. When you create a new anti-phishing policy, a blank value means the default quarantine policy is used to define the historical capabilities for messages that were quarantined by that verdict (DefaultFullAccessPolicy for all impersonation detection types). Admins can create and select custom quarantine policies that define less restrictive or more restrictive capabilities for users in the default or custom anti-phishing policies. For more information, see Quarantine policies. |
|||
If message is detected as an impersonated user TargetedUserProtectionAction |
Don't apply any action NoAction |
Quarantine the message Quarantine |
Quarantine the message Quarantine |
|
If message is detected as an impersonated domain TargetedDomainProtectionAction |
Don't apply any action NoAction |
Quarantine the message Quarantine |
Quarantine the message Quarantine |
|
If mailbox intelligence detects an impersonated user MailboxIntelligenceProtectionAction |
Don't apply any action NoAction |
Move message to the recipients' Junk Email folders MoveToJmf |
Quarantine the message Quarantine |
|
Show user impersonation safety tip EnableSimilarUsersSafetyTips |
Off $false |
Selected $true |
Selected $true |
|
Show domain impersonation safety tip EnableSimilarDomainsSafetyTips |
Off $false |
Selected $true |
Selected $true |
|
Show user impersonation unusual characters safety tip EnableUnusualCharactersSafetyTips |
Off $false |
Selected $true |
Selected $true |
EOP anti-phishing policy settings in Microsoft Defender for Office 365
These are the same settings that are available in anti-spam policy settings in EOP.
Safe Attachments settings
Safe Attachments in Microsoft Defender for Office 365 includes global settings that have no relationship to Safe Attachments policies, and settings that are specific to each Safe Links policy. For more information, see Safe Attachments in Defender for Office 365.
Although there's no default Safe Attachments policy, the Built-in protection preset security policy provides Safe Attachments protection to all recipients (users who aren't defined in the Standard or Strict preset security policies or in custom Safe Attachments policies). For more information, see Preset security policies in EOP and Microsoft Defender for Office 365.
Global settings for Safe Attachments
Note
The global settings for Safe Attachments are set by the Built-in protection preset security policy, but not by the Standard or Strict preset security policies. Either way, admins can modify these global Safe Attachments settings at any time.
The Default column shows the values before the existence of the Built-in protection preset security policy. The Built-in protection column shows the values that are set by the Built-in protection preset security policy, which are also our recommended values.
To configure these settings, see Turn on Safe Attachments for SharePoint, OneDrive, and Microsoft Teams and Safe Documents in Microsoft 365 E5.
In PowerShell, you use the Set-AtpPolicyForO365 cmdlet for these settings.
Security feature name | Default | Built-in protection | Comment |
---|---|---|---|
Turn on Defender for Office 365 for SharePoint, OneDrive, and Microsoft Teams EnableATPForSPOTeamsODB |
Off $false |
On $true |
To prevent users from downloading malicious files, see Use SharePoint Online PowerShell to prevent users from downloading malicious files. |
Turn on Safe Documents for Office clients EnableSafeDocs |
Off $false |
On $true |
This feature is available and meaningful only with licenses that are not included in Defender for Office 365 (for example, Microsoft 365 A5 or Microsoft 365 E5 Security). For more information, see Safe Documents in Microsoft 365 A5 or E5 Security. |
Allow people to click through Protected View even if Safe Documents identified the file as malicious AllowSafeDocsOpen |
Off $false |
Off $false |
This setting is related to Safe Documents. |
Safe Attachments policy settings
To configure these settings, see Set up Safe Attachments policies in Defender for Office 365.
In PowerShell, you use the New-SafeAttachmentPolicy and Set-SafeAttachmentPolicy cmdlets for these settings.
Note
As described earlier, there is no default Safe Attachments policy, but Safe Attachments protection is assigned to all recipients by the Built-in protection preset security policy (users who aren't defined in any Safe Attachments policies).
The Default in custom column refers to the default values in new Safe Attachments policies that you create. The remaining columns indicate (unless otherwise noted) the values that are configured in the corresponding preset security policies.
Security feature name | Default in custom | Built-in protection | Standard | Strict | Comment |
---|---|---|---|---|---|
Safe Attachments unknown malware response Enable and Action |
Off -Enable $false and -Action Block |
Block -Enable $true and -Action Block |
Block -Enable $true and -Action Block |
Block -Enable $true and -Action Block |
When the Enable parameter is $false, the value of the Action parameter doesn't matter. |
Quarantine policy (QuarantineTag) | AdminOnlyAccessPolicy | AdminOnlyAccessPolicy | AdminOnlyAccessPolicy | AdminOnlyAccessPolicy | Standard and Strict preset security policies use the default quarantine policy (AdminOnlyAccessPolicy with no quarantine notifications) as described in the table here. When you create a new Safe Attachments policy, a blank value means the default quarantine policy is used to define the historical capabilities for messages that were quarantined by Safe Attachments (AdminOnlyAccessPolicy with no quarantine notifications). Admins can create and select custom quarantine policies that define more capabilities for users. For more information, see Quarantine policies. |
Redirect attachment with detected attachments : Enable redirect Redirect RedirectAddress |
Not selected and no email address specified. -Redirect $false RedirectAddress is blank ( $null ) |
Not selected and no email address specified. -Redirect $false RedirectAddress is blank ( $null ) |
Selected and specify an email address. $true an email address |
Selected and specify an email address. $true an email address |
Redirect messages to a security admin for review. Note: This setting is not configured in the Standard, Strict, or Built-in protection preset security policies. The Standard and Strict values indicate our recommended values in new Safe Attachments policies that you create. |
Apply the Safe Attachments detection response if scanning can't complete (timeout or errors) ActionOnError |
Selected $true |
Selected $true |
Selected $true |
Selected $true |
Safe Links settings
Safe Links in Defender for Office 365 includes global settings that apply to all users who are included in active Safe Links policies, and settings that are specific to each Safe Links policy. For more information, see Safe Links in Defender for Office 365.
Although there's no default Safe Links policy, the Built-in protection preset security policy provides Safe Links protection to all recipients (users who aren't defined in the Standard or Strict preset security policies or in custom Safe Links policies). For more information, see Preset security policies in EOP and Microsoft Defender for Office 365.
Global settings for Safe Links
Note
The global settings for Safe Links are set by the Built-in protection preset security policy, but not by the Standard or Strict preset security policies. Either way, admins can modify these global Safe Links settings at any time.
The Default column shows the values before the existence of the Built-in protection preset security policy. The Built-in protection column shows the values that are set by the Built-in protection preset security policy, which are also our recommended values.
To configure these settings, see Configure global settings for Safe Links in Defender for Office 365.
In PowerShell, you use the Set-AtpPolicyForO365 cmdlet for these settings.
Security feature name | Default | Built-in protection | Comment |
---|---|---|---|
Block the following URLs ExcludedUrls |
Blank $null |
Blank $null |
We have no specific recommendation for this setting. For more information, see "Block the following URLs" list for Safe Links. Note: You can now manage block URL entries in the Tenant Allow/Block List. The "Block the following URLs" list is in the process of being deprecated. We'll attempt to migrate existing entries from the "Block the following URLs" list to block URL entries in the Tenant Allow/Block List. Messages containing the blocked URL will be quarantined. |
Safe Links policy settings
To configure these settings, see Set up Safe Links policies in Microsoft Defender for Office 365.
In PowerShell, you use the New-SafeLinksPolicy and Set-SafeLinksPolicy cmdlets for these settings.
Note
As described earlier, there's no default Safe Links policy, but Safe Links protection is assigned to all recipients by the Built-in protection preset security policy (users who otherwise aren't included in any Safe Links policies).
The Default in custom column refers to the default values in new Safe Links policies that you create. The remaining columns indicate (unless otherwise noted) the values that are configured in the corresponding preset security policies.
Security feature name | Default in custom | Built-in protection | Standard | Strict | Comment |
---|---|---|---|---|---|
URL & click protection settings | |||||
Action on potentially malicious URLs within Emails | |||||
On: Safe Links checks a list of known, malicious links when users click links in email EnableSafeLinksForEmail |
Not selected $false |
Selected $true |
Selected $true |
Selected $true |
|
Apply Safe Links to email messages sent within the organization EnableForInternalSenders |
Not selected $false |
Not selected $false |
Selected $true |
Selected $true |
|
Apply real-time URL scanning for suspicious links and links that point to files ScanUrls |
Not selected $false |
Selected $true |
Selected $true |
Selected $true |
|
Wait for URL scanning to complete before delivering the message DeliverMessageAfterScan |
Not selected $false |
Selected $true |
Selected $true |
Selected $true |
|
Do not rewrite URLs, do checks via Safe Links API only DisableURLRewrite |
Not selected $false |
Selected $true |
Not selected $false |
Not selected $false |
|
Do not rewrite the following URLs in email DoNotRewriteUrls |
Blank $null |
Blank $null |
Blank $null |
Blank $null |
We have no specific recommendation for this setting. Note: Entries in the "Do not rewrite the following URLs" list are not scanned or wrapped by Safe Links during mail flow. Use allow URL entries in the Tenant Allow/Block List so URLs are not scanned or wrapped by Safe Links during mail flow and at time of click. |
Action for potentially malicious URLs in Microsoft Teams | |||||
On: Safe Links checks a list of known, malicious links when users click links in Microsoft Teams EnableSafeLinksForTeams |
Not selected $false |
Selected $true |
Selected $true |
Selected $true |
|
Action for potentially malicious URLs in Microsoft Office apps | |||||
On: Safe Links checks a list of known, malicious links when users click links in Microsoft Office apps EnableSafeLinksForOffice |
Selected $true |
Selected $true |
Selected $true |
Selected $true |
Use Safe Links in supported Office 365 desktop and mobile (iOS and Android) apps. For more information, see Safe Links settings for Office apps. |
Click protection settings | |||||
Track user clicks TrackClicks |
Selected $true |
Selected $true |
Selected $true |
Selected $true |
|
Let users click through to the original URL AllowClickThrough |
Selected $true |
Selected $true |
Not selected $false |
Not selected $false |
Turning off this setting (setting AllowClickThrough to $false ) prevents click through to the original URL. |
Display the organization branding on notification and warning pages EnableOrganizationBranding |
Not selected $false |
Not selected $false |
Not selected $false |
Not selected $false |
We have no specific recommendation for this setting. Before you turn on this setting, you need to follow the instructions in Customize the Microsoft 365 theme for your organization to upload your company logo. |
Notification | |||||
How would you like to notify your users? CustomNotificationText UseTranslatedNotificationText |
Use the default notification text Blank ( $null ) $false |
Use the default notification text Blank ( $null ) $false |
Use the default notification text Blank ( $null ) $false |
Use the default notification text Blank ( $null ) $false |
We have no specific recommendation for this setting. You can select Use custom notification text ( -CustomNotificationText "<Custom text>" ) to enter and use customized notification text. If you specify custom text, you can also select Use Microsoft Translator for automatic localization (-UseTranslatedNotificationText $true ) to automatically translate the text into the user's language. |
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