KB1794: Insufficient Storage for VSS Error "0x8004231F or ...
www.veeam.com › kb1794Jul 22, 2013 · Create and then delete a shadow copy of each volume, one at a time. To access the GUI, right click any volume and choose Configure Shadow Copies. On older operating systems, this may instead be a tab in Properties. In the Shadow Copies utility: Select a volume; Click Create Now; If this is successful, select the shadow copy and click Delete Now;
KB1680: VSS Timeout when backing up Exchange VM
https://www.veeam.com/kb168028.09.2012 · The backup of an Exchange server VM fails with: Unfreeze error:[Backup job failed] Cannot create shadow copy of the volumes containing writer’s data A VSS critical writer has failed. Writer name: [Microsoft Exchange Writer]. Class ID: [{76fe1ac4-15f7-4bcd-987e-8e1acb462fb7}]. Instance ID: [{0db23250-4d1e-42c1-8d14-2be32f448184}].