# Backup Failed: Agent failed to process method {ReFs.SetFileIntegrity}.

### <span class="C9DxTc ">Error</span>

<span class="C9DxTc ">When running a backup job you receive the following error:</span>

<span class="C9DxTc ">Processing \[SERVER NAME\] Error: Incorrect function. Agent failed to process method {ReFs.SetFileIntegrity}.</span>

### <span class="C9DxTc ">Fix</span>

<span class="C9DxTc ">Run this to disable fast clone:</span>

> <span class="C9DxTc ">New-ItemProperty -Path 'HKLM:\\SOFTWARE\\Veeam\\Veeam Backup and Replication\\' -Name 'UseCifsVirtualSynthetic' -Value '0' -PropertyType DWORD -Force</span>

<span class="C9DxTc ">To undo fix:</span>

> <span class="C9DxTc ">Remove-ItemProperty -Path "HKLM:\\SOFTWARE\\Veeam\\Veeam Backup and Replication\\" -Name "UseCifsVirtualSynthetic"</span>

<span class="C9DxTc ">Ref: </span>[<span class="C9DxTc aw5Odc ">https://www.veeam.com/kb4381</span>](https://www.veeam.com/kb4381)