When running a job with VSS, you receive an error similar to the following one:
VSSControl: Index failed Error: Cannot write file in CFileWriter::WriteLongLong Win32 error:There is not enough space on the disk. Code: 112 Freezing guest operating system VSSControl: -2147024784 Backup job failed. Cannot create a shadow copy of the volumes containing writer's data. Cannot serialize a VSS metadata. Cannot save the Backup Components Document. Path: [C:\WINDOWS\VeeamVssSupport\metadata\VSS\BackupComponents.xml]. Cannot store a XML document at the specified location: [C:\WINDOWS\VeeamVssSupport\metadata\VSS\BackupComponents.xml]. COM error: There is not enough space on the disk. Code: 0x80070070
There is not enough disk space in the guest OS to run the agent and start VSS.
You need to free up disk space on the system of the VM you are trying to back up. Try to free up at least 1GB of space. After this, run the job again.