Datto Windows Agent: Backups Fail with 0x00000000 and 0xc000009a

Issue

When you try to start a backup for a system protected by the Datto Windows Agent, you encounter backup failures with error codes 0x00000000 or 0xc000009a, and one of the following errors:

  • "Backup Exception: Could not set up volume snapshot set"
  • "Snapshot failed. Error: 31 - Could not take Datto snapshot set."

Environment

  • Datto Windows Agent

Cause

This error is the result of an allocation failure when trying to get memory from the non-paged kernel memory pool. Other applications or drivers on the system may be using so much memory that there isn't enough left for the Datto driver.

The amount of memory the Datto snapshot driver uses is related to the sum of the volume sizes of the volumes being backed up. The larger this sum, the more non-paged pool memory is required.

This issue frequently occurs on 32-bit systems due to the limited non-paged pool available. If a system is running a 64-bit OS, the issue is likely a lack of available system memory. Most 64-bit versions of Windows can use up to 128 GB of available system RAM for the non-paged pool.

Resolution

64-bit systems

Preserve or increase the total system memory available. Datto recommends keeping at least 1 GB of system memory free for backups to succeed.

32-bit systems

  • Ensure that the protected system has the most total RAM available. In most cases this will be between 3.5 GB to 4 GB of physical RAM.
  • Reduce the size of the connected disks on the protected system.
  • Replace the system with a 64-bit equivalent.

See the article regarding the generic snapshot error.

Review the Additional Resources section of this article for more information about nonpaged memory and its limitations.

Additional Resources