I have got a Sony laptop which is running on Windows XP. I dont know when this problem started, but just sometime back I noticed that it will not hibernate. When I click on the hibernate button the the system goes to the "preparing to hibernate screen" and then goes back to the normal windows screen. Also, the computer will not hibernate on its own if the power management properties are set for it to go into hibernation after so long. The laptop will go into standby mode properly. I have also run antivirus software on this pc but everything seems to be clean. Can anyone give me some ideas how to solve this issue? Thanks.