When you hibernate your computer, instead of shutting down and restarting your computer, Windows saves the contents of the system’s memory to the hiberfil.sys (onto the hard drive) and then turns off most of your hardware. As a result, the size of the hiberfil.sys file will always equal the amount of physical memory in your system. If you are tight on disk space and don’t whish to use hibernation, the to recapture the space that Windows uses for the hiberfil.sys file, perform the following steps:
- Start the Control Panel Power Options applet by going to Start >> Settings >> Control Panel >> and click Power (or Start >> Run >> Powercfg.cpl).
- Select the Hibernate tab, clear the “Enable hibernation” check box, then click OK; although you might think otherwise, selecting Never under the “System hibernates” option on the Power Schemes tab doesn’t delete the hiberfil.sys file.
Windows will remove the “System hibernates” option from the Power Schemes tab and delete the hiberfil.sys file.
NB: Changing the Power Scheme to “Always On,” does not disable Hibernation nor delete hiberfil.sys.