Reauthorising Veeam Data Cloud for Microsoft 365

You may need to reauthorise Veeam Data Cloud access to your Microsoft 365 tenant. This may be required in the following cases:

• If you have accidentally removed authorisation for Veeam Data Cloud to access your Microsoft 365 data
• If you see the following error message in your backup logs: The identity of the calling application could not be established.

To reauthorise Veeam Data Cloud, do the following:  

1. Log in to Veeam Data Cloud for Microsoft 365 with an administrator account.
2. In the main menu, click Settings.
3. In the Settings menu, click System.
4. Click Reauthorise.