Windows Server Backup is timing out during shadow copy creation since it is taking more than 10 minutes.
Try increasing the timeout value to 20 minutes and see if that fixes this issue
This involves updating a registry key. Hence please do this carefully.
– Run regedit.exe and navigate to L”HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\SPP”
– Create a new Registry value of type DWORD with name “CreateTimeout”
– Change value to 12000000(2*10*60*1000 = 20 mins) in decimal
Re-run backup and check if it succeeds now.