Microsoft released its November Windows Update Rollup for Windows Server 2012 (KB3000853) this week and it was quickly discovered that it was negatively impacting Hyper-V backups in Windows Server 2008 R2 and Windows Server 2012. An update was also released for Windows Server 2012 R2 (KB3000850) and it’s currently unclear whether or not those Hyper-V backups are affected.
If you receive an error in backing up your Hyper-V, you can either uninstall the update or apply the hotfix.
All virtual backup solutions are affected by this. If you use Veeam, your error message will look similar to this:
UPDATE: Veeam released a v8 update rollup that fixes these issues with Hyper-V backup.