Block emails which go outside organisation

Question

Hello all
Can you please kindly advise if there is any rule which I can set up to avoid users from sending emails outside the company.

The email should first go to an independent authorizer and depending whether it is rejected or accepted then the email should go out from the organization.

I need this logic in office 365.
If such a functionality is not available then can any code be run which can be used alongside outlook to get this feature.

Lloyd
Lloyd.bangera@Stuff .com

Answer 1

You may use mail flow rules to take action on messages that flows through your exchange online organization.

Refer: https://learn.microsoft.com/en-us/exchange/security-and-compliance/mail-flow-rules/mail-flow-rules#mail-flow-rule-components

https://learn.microsoft.com/en-us/exchange/security-and-compliance/mail-flow-rules/manage-mail-flow-rules

https://www.codetwo.com/admins-blog/how-to-prevent-office-365-users-from-sending-emails-outside-organization/

Hope this helps.

Answer 2

@Sreeju Nair .. Thank you very much for your reply. As I am not much of a tech person. I want to understand if the rules will allow me to do the below steps.

Example

1. Email sent externally by employee
2. Notification goes to manager who looks at the email and then either rejects or approves
3. If approved then email will go out automatically
4. If rejected then back to user stating it has been rejected

What functionality in office 365 does one have to switch on to get these rules. Not everyone is an admin who will have access to the admin tool to change rules

Answer 3

@lloyd bangera

You could take the steps below to create transport rule:

1. Login Exchange online admin center.
2. Create a new Transport rule from "Mail Flow→Rules"
3. Click more options:
   
4. Then you will create a transport rule as below:
   

If someone tries to send emails to external of your tenant, this email will be forwarded to the specific user:

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Answer 4

@Sreeju Nair thank you very much. Super helpfull. Managed to get the business to work on these ideas. Thank you very very much again.