Synchronisation was disabled due to an authorisation error
If you see the message “Synchronization was disabled due to an Authorization error”, you can usually find more details about the error by going to:
Preferences → Exchange Sync → My Sync Status → Issues
Individual User Account
Below are the typical steps we recommend to resolve an Authorization Error.
1. Go to Start → Preferences.
2. Navigate to Integrations → Exchange Sync.
3. Once the screen loads (see screenshot), click Refresh.
4. A new window will appear prompting you to authorize your Microsoft account. Enter your Office 365 email address and password to continue.
Note
If the Window does not appear, please ensure that pop-ups are not blockers in your browser.
Impersonation User
You could get an Authorization error too if the Mailbox type set has issues, for example if the Mailbox type is set to Microsoft 365 OAuth (ESW API) – App-Only logon , please ask you Microsoft Admin to too look for any Mailbox Issues ( eg The user’s mailbox might be inactive, deleted, or corrupted), licensing, and any security policies that might block the app-only connection.
Note
Recently Microsoft have deprecated Basic Authentication (Microsoft Exchange and Direct Logon) as detailed here – https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/deprecation-of-basic-authentication-exchange-online. Further info on switching authentication type can be found here https://www.workbooks.com/help/how-change-authentication-setup-wess.