Enable External Email Identification Flags

External Email Identification Flags enable Outlook and Outlook Web products to display a warning when an email is from an external source. The flags must be set using the Exchange Online PowerShell Commandlets.

Enable External Email Identification Flags

1. Connect to Exchange Online.
   1. Import-Module ExchangeOnlineManagment
   2. Connect-ExchangeOnline -UserPrincipalName your-email-or-username

2. Enable the External Email Flag.

   1. Set-ExternalInOutlook -Enabled $true

Disable External Email Identification Flags

1. Connect to Exchange Online.
   1. Import-Module ExchangeOnlineManagment
   2. Connect-ExchangeOnline -UserPrincipalName your-email-or-username

2. Enable the External Email Flag.

   1. Set-ExternalInOutlook -Enabled $false

Resources

• Set-ExternalInOutlook (ExchangePowerShell) | Microsoft Learn