Random Server Freeze during Virtual Machines snapshot

Hi

We are actually using BackupExec 2014 with Deduplication Option

Sometimes, during virtual Backup of Vsphere 5.1 virtual machines, Backup Server just freeze and stop responding.

When connecting through ILO, it's still powered on, just freezed on Windows 2008 screen. Only way is to reset server to restart all

Freezes are really random, it can happen three days in a row. But there can be 15 days without any freeze.

Freezes ONLY happen during a virtual machine snapshot operation.

It happened with BackupExec 2012 too, I hoped that upgrading to 2014 would solve this problem :(