Unable to Back up On-Demand Files (code 1633)

Situation

A backup plan failed with the following error message: On-Demand files cannot be backed up due to known Microsoft issue. Try to fix OneDrive

Cause

This error occurs due to known Microsoft issue related to OneDrive app. The error is caused by a problem with OneDrive sync. It could be in case of the folder you are trying to access is corrupted, or there is an issue with other system files preventing OneDrive from syncing successfully.

Solutions

Solution 1

Reset or re-sync OneDrive app as described in the following Microsoft article.

Solution 2

Exclude affected On-Demand files from the backup dataset.