Recently, while I was trying to clear off space on the system drive of a client’s server, I found that the file hiberfil.sys (hibernation File) existed there, and was the same size as the page file (which was about 10GB).  I was curious as to why this was there, as any decent system administrator knows that there is no reason to turn on hibernation on a server, as it is never used, and wastes a lot of space.  After a little research, I found that in Windows Server 2008,  hibernation is enabled by default as it is in Vista and 7 to allow for Hybrid Sleep Mode, which is supposed to restore the system in the event of a power failure.  I have not tested how well this works, but I am not sure as to why they would turn this option on by default, as servers are generally protected by a UPS and it uses up valuable hard disk space.  Anyway, here is a quick and easy command to turn it off on Windows Vista, Windows 7, and Server 2008.

In the event that you want to turn it back on, here is the command for that.

Here is the Microsoft article for this fix.