Compliance: Always mark emails from guests as “External” in Outlook
Since Ignite at the beginning of March 2021 it is now possible to tag external email. I will explain how this works in this post:
Outlook – mark External with “External” Tag
This has the advantage that it is very good for compliance. Users receive the label External in mobile, OWA and Outlook (latest version) and see that the email comes from External. This can then eliminate the need for the additional “External” header per message policy. Studies showing that tagging within an email does not have the effect it should. Users do not see and recognize that the email was sent from an external party, thus preventing a phishing attack.
- Exchange Online
- not available for Exchange OnPremises
- Exchange PS Module V2
- Tenant the function must already be available, otherwise an error of the PS script occurs.
######External marking##### #Activate PS Scripting on your PC Get-ExecutionPolicy Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser #ExchangeModule V2 install and import #https://www.powershellgallery.com/packages/ExchangeOnlineManagement/2.0.4 Import-Module ExchangeOnlineManagement Install-Module ExchangeOnlineManagement Update-Module ExchangeOnlineManagement ##control Get-Module Get-Module -ListAvailable #Connect with Exchange Online Connect-ExchangeOnline -UserPrincipalName emailadresse #status contol #https://docs.microsoft.com/en-us/powershell/module/exchange/get-externalinoutlook Get-ExternalInOutlook #Activate the External Tag #https://docs.microsoft.com/en-us/powershell/module/exchange/set-externalinoutlook?WT.mc_id=M365-MVP-5003860&view=exchange-ps Set-ExternalInOutlook -Enabled $true #activate only for a few Set-ExternalInOutlook -AllowList email@example.com,firstname.lastname@example.org
source: Microsoft Ignite 2021 content