365 UPN & External Accounts

Copper Contributor

Hello, my company only uses Office 365 we do not have a local active directory. We have two UPN's linked to our 365, the current one which is too long and the new one which we want to migrate over to.

My question is what happens to accounts that are linked to external applications etc that have been created using our current UPN when we migrate over. Will the user be able to log in to these external accounts with the new UPN, will they still have to log in with the current UPN, will it lock the account when the UPN is changed...

I know there are some apps/accounts that have SSO's and when the UPN is changed it creates a whole new account on their system with that new UPN and the staff on that end will have to manually sort it but any information or advice you can share with me would be greatly appreciated!

1 Reply



It depends on what kind of application, say for example, on-prem Skype for business may affected since UPN will be used as identifier