Guide for fixing a Windows Server Backup Failed There is not enough disk space to create the volume shadow copy
This error can occur if Windows Server Backup tries to create Volume shadow copies on disk partitions that are very small (typically less than 500MB). You may find that your windows server has one or more very small partitions eg for the Recovery Partition. These can cause Windows Server Backup to fail as there is not enough free space in these partitions to create the VSS copy.
Follow these steps to work-around this issue:
On the server with this issues, open a command prompt as admin and run mountvol to get the GUIDs for the volumes on the computer.
You will get an output something like this:
Possible values for VolumeName along with current mount points are:
\\?\Volume{85df9fc1-d754-40cd-947d-5eebea1f3ae2}\ *** NO MOUNT POINTS ***
\\?\Volume{187c7f14-6dbc-4369-a180-9cc35d309905}\ C:\
\\?\Volume{a9b4c7fb-9aac-4947-866b-851298cb39fa}\ *** NO MOUNT POINTS ***
\\?\Volume{51b9029f-3aab-4c48-863c-cfcaa16600f1}\ *** NO MOUNT POINTS ***
Once you've got the GUIDs for the volumes, try to identify which volume is causing the backup error . In my experience, it's usually the first volume in the list. Adjust the path for it's shadow copy storage using this command:
vssadmin add shadowstorage /for=\\?\Volume{85df9fc1-d754-40cd-947d-5eebea1f3ae2}\ /on=c: /maxsize=500MB
If this command doesn't work, you may not have selected the correct GUID - try a different one and re-run the backup
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