Issue
When trying to log in to activate Microsoft Office 365 apps on a Windows computer, you may get an error that the login failed because another user is already logged in, despite logging in correctly and with an active account.
Resolution
- Open a Microsoft Office 365 app, such as Word
- Go to the File menu and select Account on the left
- Click Sign Out
- Close and reopen the app
- Choose to sign in to activate Microsoft Office 365 again