2008 R2 - Fresh install - ASR writer fails on backup

I have set up a few new Server 2008 R2 machines with Hyper V role recently and every time I run a backup that includes System State, the backup will fail and the ASR Writer will show a state of 7 - Failed.

This happens with Windows Backup or Backup Exec 2012. Symantec says it is a Microsoft issue. Microsoft says it is a Symantec issue. I don't care who the issue is with, I want clean backups!

I don't see anything in the logs.