New-SafeAttachmentRule
This cmdlet is available only in the cloud-based service.
Use the New-SafeAttachmentRule cmdlet to create safe attachment rules in your cloud-based organization.
For information about the parameter sets in the Syntax section below, see Exchange cmdlet syntax.
Syntax
New-SafeAttachmentRule
[-Name] <String>
-SafeAttachmentPolicy <SafeAttachmentPolicyIdParameter>
[-Comments <String>]
[-Confirm]
[-Enabled <Boolean>]
[-ExceptIfRecipientDomainIs <Word[]>]
[-ExceptIfSentTo <RecipientIdParameter[]>]
[-ExceptIfSentToMemberOf <RecipientIdParameter[]>]
[-Priority <Int32>]
[-RecipientDomainIs <Word[]>]
[-SentTo <RecipientIdParameter[]>]
[-SentToMemberOf <RecipientIdParameter[]>]
[-WhatIf]
[<CommonParameters>] Description
You need to specify at least one condition for the rule.
A safe attachment policy can be assigned only to one safe attachment rule.
Safe Attachments is a feature in Microsoft Defender for Office 365 that opens email attachments in a special hypervisor environment to detect malicious activity. For more information, see Safe Attachments in Defender for Office 365.
Important
Different types of recipient conditions use AND logic (the recipient must satisfy all specified conditions). Different types of recipient exceptions use OR logic (the recipient must satisfy any of the specified exceptions). For more information, see Safe Attachments policy settings.
You need to be assigned permissions before you can run this cmdlet. Although this topic lists all parameters for the cmdlet, you may not have access to some parameters if they're not included in the permissions assigned to you. To find the permissions required to run any cmdlet or parameter in your organization, see Find the permissions required to run any Exchange cmdlet.
Examples
Example 1
New-SafeAttachmentRule -Name "Research Department Attachment Rule" -SafeAttachmentPolicy "Research Block Attachments" -SentToMemberOf "Research Department" -ExceptIfSentToMemberOf "Research Department Managers"This example creates a new safe attachment rule named Research Department Attachment Rule with the following conditions:
- The rule is associated with the safe attachment policy named Research Block Attachments.
- The rule applies to members of the group named Research Department.
- The rule doesn't apply to members of the group named Research Department Managers.
Parameters
-Comments
The Comments parameter specifies informative comments for the rule, such as what the rule is used for or how it has changed over time. The length of the comment can't exceed 1024 characters.
| Type: | String |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-Confirm
The Confirm switch specifies whether to show or hide the confirmation prompt. How this switch affects the cmdlet depends on if the cmdlet requires confirmation before proceeding.
- Destructive cmdlets (for example, Remove-* cmdlets) have a built-in pause that forces you to acknowledge the command before proceeding. For these cmdlets, you can skip the confirmation prompt by using this exact syntax:
-Confirm:$false. - Most other cmdlets (for example, New-* and Set-* cmdlets) don't have a built-in pause. For these cmdlets, specifying the Confirm switch without a value introduces a pause that forces you acknowledge the command before proceeding.
| Type: | SwitchParameter |
| Aliases: | cf |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-Enabled
The Enabled parameter specifies whether the rule is enabled. Valid values are:
- $true: The rule is enabled. This is the default value.
- $false: The rule is disabled.
In the properties of the rule, the value of this parameter is visible in the State property.
| Type: | Boolean |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-ExceptIfRecipientDomainIs
The ExceptIfRecipientDomainIs parameter specifies an exception that looks for recipients with email addresses in the specified domains. You can specify multiple domains separated by commas.
| Type: | Word[] |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-ExceptIfSentTo
The ExceptIfSentTo parameter specifies an exception that looks for recipients in messages. You can use any value that uniquely identifies the recipient. For example:
- Name
- Alias
- Distinguished name (DN)
- Canonical DN
- Email address
- GUID
You can enter multiple values separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Value1","Value2",..."ValueN".
| Type: | RecipientIdParameter[] |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-ExceptIfSentToMemberOf
The ExceptIfSentToMemberOf parameter specifies an exception that looks for messages sent to members of distribution groups, mail-enabled security groups, or sent to Microsoft 365 Groups. You can use any value that uniquely identifies the group. For example:
- Name
- Alias
- Distinguished name (DN)
- Canonical DN
- Email address
- GUID
You can enter multiple values separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Value1","Value2",..."ValueN".
If you remove the group after you create the rule, no exception is made for messages that are sent to members of the group.
| Type: | RecipientIdParameter[] |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-Name
The Name parameter specifies a unique name for the safe attachment rule. If the value contains spaces, enclose the value in quotation marks (").
| Type: | String |
| Position: | 1 |
| Default value: | None |
| Required: | True |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-Priority
The Priority parameter specifies a priority value for the rule that determines the order of rule processing. A lower integer value indicates a higher priority, the value 0 is the highest priority, and rules can't have the same priority value.
Valid values and the default value for this parameter depend on the number of existing rules. For example, if there are 8 existing rules:
- Valid priority values for the existing 8 rules are from 0 through 7.
- Valid priority values for a new rule (the 9th rule) are from 0 through 8.
- The default value for a new rule (the 9th rule) is 8.
If you modify the priority value of a rule, the position of the rule in the list changes to match the priority value you specify. In other words, if you set the priority value of a rule to the same value as an existing rule, the priority value of the existing rule and all other lower priority rules after it is increased by 1.
| Type: | Int32 |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-RecipientDomainIs
The RecipientDomainIs parameter specifies a condition that looks for recipients with email addresses in the specified domains. You can specify multiple domains separated by commas.
| Type: | Word[] |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-SafeAttachmentPolicy
The SafeAttachmentPolicy parameter specifies the safe attachment policy that's associated with this safe attachment rule. The rule defines the conditions, and the policy defines the actions.
You can use any value that uniquely identifies the policy. For example:
- Name
- Distinguished name (DN)
- GUID
You can't specify a safe attachment policy that's already associated with another safe attachment rule.
| Type: | SafeAttachmentPolicyIdParameter |
| Position: | Named |
| Default value: | None |
| Required: | True |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-SentTo
The SentTo parameter specifies a condition that looks for recipients in messages. You can use any value that uniquely identifies the recipient. For example:
- Name
- Alias
- Distinguished name (DN)
- Canonical DN
- Email address
- GUID
You can enter multiple values separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Value1","Value2",..."ValueN".
| Type: | RecipientIdParameter[] |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-SentToMemberOf
The SentToMemberOf parameter specifies a condition that looks for messages sent to members of distribution groups, mail-enabled security groups, or sent to Microsoft 365 Groups. You can use any value that uniquely identifies the group. For example:
- Name
- Alias
- Distinguished name (DN)
- Canonical DN
- Email address
- GUID
You can enter multiple values separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Value1","Value2",..."ValueN".
If you remove the group after you create the rule, no action is taken on messages that are sent to members of the group.
| Type: | RecipientIdParameter[] |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |
-WhatIf
The WhatIf switch simulates the actions of the command. You can use this switch to view the changes that would occur without actually applying those changes. You don't need to specify a value with this switch.
| Type: | SwitchParameter |
| Aliases: | wi |
| Position: | Named |
| Default value: | None |
| Required: | False |
| Accept pipeline input: | False |
| Accept wildcard characters: | False |
| Applies to: | Exchange Online |