Unable to exclude files from snapshot: Shadow Copy Optimization Writer timed out

Veeam Endpoint Backup;Veeam Agent for Microsoft Windows
1.1.2, 2.x
Last Modified:


During a backup job Veeam Endpoint Backup returns the following warning:

Unable to exclude files from snapshot: Shadow Copy Optimization Writer timed out

The warning occurs in the following scenario: file-level backup is selected as backup mode, then a whole volume is selected, and a number of folders is explicitly excluded from backup.


The issue is caused by MS Copy Optimization Writer timeout due to a large number of excluded files. In such cases the Application Event Log on the affected workstation may contain entries similar to the one below:

Source:        VSS
Event ID:      8220
Level:         Information

   OnPostSnapshot event
   PostSnapshot Event

   Execution Context: Shadow Copy Optimization Writer
   Writer Name: Shadow Copy Optimization Writer


Two possible approaches are suggested.


1. Reduce the number of excluded folders until the warning is no longer displayed.
2. Rather than selecting a whole volume within file-level backup, it is recommended to select only the specific folders, that need to be processed.

More Information

If you have further questions, open a support case as follows:

  1. Right-click the Veeam Endpoint Backup / Veeam Agent for Windows icon in the system tray and select Control Panel.
  2. Click the Support link at the top of the window.
  3. Click Technical Support to submit a support case to the Veeam Support Team directly from the product.

Please be aware that we’re making changes which will restrict access to product updates for users without an active contract.


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