Follow the article :
http://support.microsoft.com/kb/920730
In nutshell:
Activate Hibernation( Run following command)
powercfg.exe /hibernate on
De-Activate Hibernation
powercfg.exe /hibernate off
http://support.microsoft.com/kb/920730
In nutshell:
Activate Hibernation( Run following command)
powercfg.exe /hibernate on
De-Activate Hibernation
powercfg.exe /hibernate off