What is hiberfil.sys ?

Windows has two power management modes that you can choose from: one is Sleep Mode, which keeps the PC running in a low power state so you can almost instantly get back to what you were working on. The other is Hibernate mode, which completely writes the memory out to the hard drive, and then powers the PC down entirely, so you can even take the battery out, put it back in, start back up, and be right back where you were.

Hibernate mode uses the hiberfil.sys file to store the the current state (memory) of the PC, and since it’s managed by Windows, you can’t delete the file.

Disable Hibernate / Delete hiberfil.sys in Windows 7 or Vista

You’ll need to open an administrator mode command prompt by right-clicking on the command prompt in the start menu, and then choosing Run as Administrator. Once you’re there, type in the following command:

powercfg -h off

You should immediately notice that the Hibernate option is gone from the Shut down menu. You’ll also notice that the file is magically gone!

Disabling Hibernate Mode in Windows XP

It’s a lot easier in Windows XP to get rid of Hibernate mode. Just head into Control Panel –> Power Options, and then find the Hibernate tab. Uncheck the box, reboot your PC, and then you can delete the hiberfil.sys file.