Disable Windows Hibernate function/ Delete hiberfil.sys
Windows uses the file hiberfil.sys, stored in the root
folder of your hard disk (usually in C:\), to hold your hibernation data i.e.
snap shot of your current session (all your running programs, open files,
etc.).
It is normally of the same size as the amount of installed
memory (RAM).
If you have 4 GB of RAM, You’ll see a 4 GB hiberfil.sys file
on your hard disk that Windows won’t let you delete. Windows creates the
hiberfil.sys file automatically when you turn on the Hibernate feature.
If you're running low on hard drive space and never use the
Hibernate feature, hiberfil.sys is unnecessarily eating up your hard disk
space.
The easy way to disable Hibernate, and thus removing
hiberfil.sys, on Windows Vista and Windows 7, is through the command prompt.
Below are the steps:
1. Open a command prompt with administrative
privileges.
2. Type the command "powercfg -h off" (without
semicolon) and hit Enter.
3. Exit the command prompt.
Re-enable Windows
Hibernate
To turn the Hibernate function back on, simply enter
"powercfg -h on" at a command prompt with administrative privileges.