Scratching my head here with my Windows Server 2008 R2 Server. I recently performed some updates and was able to reboot after production. I noticed after the Server made its return that our system volume on our shared directory had cleared a large portion of space. I have verified the contents on both our home and shared directories and all seems fine. Inside of this drive we have the obvious system volume information file and also a Backup Exec AOF Store. I am wondering if cache from one of these two had built, performing updates and a reboot cleared that cache. Can anyone confirm this or have they seen anything related to this? At first glance the cold sweats sink in but investigating has turned back mostly normal expectations. I am currently running a server anti-virus scan but do not expect anything to be found. Any suggestions what may have caused this?