Opti9 incident

Veeam Backup for Microsoft 365 - SharePoint or OneDrive Backup fails with 'Cannot complete this action'

Minor Resolved View vendor source →

Opti9 experienced a minor incident on July 23, 2026 affecting Veeam Backup for Microsoft 365 - gsc3-m-portal and Veeam Backup for Microsoft 365 - pub1-par-vbo and 1 more component, lasting 6d 22h. The incident has been resolved; the full update timeline is below.

Started
Jul 23, 2026, 07:43 PM UTC
Resolved
Jul 30, 2026, 06:42 PM UTC
Duration
6d 22h
Detected by Pingoru
Jul 23, 2026, 07:43 PM UTC

Affected components

Veeam Backup for Microsoft 365 - gsc3-m-portalVeeam Backup for Microsoft 365 - pub1-par-vboVeeam Backup for Microsoft 365 - office365Veeam Backup for Microsoft 365 - portal-m-gscVeeam Backup for Microsoft 365 - yow01-mVeeam Backup for Microsoft 365 - yow02-mVeeam Backup for Microsoft 365 - yow03-mVeeam Backup for Microsoft 365 - yow04-m

Update timeline

  1. identified Jul 23, 2026, 07:43 PM UTC

    Opti9 has identified an issue affecting a subset of OneDrive and SharePoint backups, where not all items may be successfully protected due to an error returned by the Microsoft API. For affected items, Veeam may display the following warning: "Cannot complete this action. Please try again. Total count of failed items: X" Additional information is available in Veeam Knowledge Base article KB4793: https://www.veeam.com/kb4793 Opti9 is actively monitoring the situation and is awaiting further guidance from Microsoft and/or Veeam. This incident will be updated as additional information becomes available.

  2. resolved Jul 30, 2026, 06:42 PM UTC

    This issue has been resolved. If you are still experiencing issues please reach out to our Support team.