Microsoft 365 Backup Job is Locked

Product version: 11.0

Last modified: 24 July 2025

Problem

When running a Backup or Backup Copy Job, the following error may appear:

Error 330 – The backup is locked by the "discover backup repository" action

Reason: target object(s) are in use by "Backup service: repository discovery".

Background

During the repository discovery process, backup files are temporarily locked to prevent conflicting access. If a Backup Job or other operation tries to access a backup that is currently being refreshed, the job cannot lock the backup object and fails with Error 330.

Solution

To resolve this issue, do the following:

  1. Prevent auto-refresh of repositories from overlapping with scheduled backup or backup copy jobs. For more information, refer to System Settings.

  2. Consider adjusting the repository discovery schedule or disabling automatic refresh during peak job execution hours.

  3. Ensure the Transporter has sufficient resources and is not overloaded. Monitor CPU and memory usage on the Transporter host to detect performance bottlenecks.

  4. If the problem persists, create a Support Bundle, including relevant job logs and system configuration.