Mr Google found:
Indexing Windows components failed - Index Error - restarting VSS was enough
VSSControl: Index failed error: There is not enough space on disk - free up disk space
My first thought was not enough space for the shadow copy.
My next thought was check system with DISM and SFC - see Windows Central or Microsoft documentation for Use the System File Checker tool to repair missing or corrupted system files and Fix Windows Update errors by using the DISM or System Update Readiness tool
Then I thought maybe do a virus scan but that is pushing it.
Someone with more windows knowledge may have better suggestions but looking at the system for problems can’t hurt.
You should include the version of the client system.