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Recently I increased size of my c: where windows7 was installed

before resizing the partition, windows was hibernating properly but now I am not able to hibernate or sleep.

My motherboard support s1 & s3 sleep states (used powercfg.exe Tried disabling and enabling hibernate but doesn't worked

When I hibernate or sleep the display goes off for 5-6 seconds and login screen opens up

I want to know whether resizing the partition can cause such problem or any other thing that has caused this problem

Now if i enable hibernate, sleep(standby mode) doesn't work but if i disable hibernate my sleep works properly

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up vote 1 down vote accepted

The Windows system partition has to be active for hibernation to work.

  1. Press Win+R keys to open the Run dialog and type diskmgmt.msc
  2. Right-click on the Windows system partition (usually C:) and set "Mark Partition as Active"
  3. Reboot
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Thanx a lot it worked for me as well thank you – KB5 Aug 23 '12 at 20:45

Resizing your OS partition can prevent hibernation mode from working if there isn't enough space to create the hibernation file. If you look at hidden system files on the root of the C: drive on any system on which hibernation is enabled, you'll see a file called hiberfil.sys. This is the file to which your RAM is suspended when you enter hibernation mode.

In Windows 7, the hibernation file is by default compressed to a size equal to 75% of the system's physical memory.

Check to see if the file is there (dir /a *.sys from the root of C:); if not, verify that you have enough free space in the partition (i.e. 75% of physical memory) for the OS to create this file. If there isn't enough space, this is your problem; you'll need to clear out space or enlarge the partition to accommodate the hibernation file.

Unfortunately, the file has to be on the boot partition in order for the Windows bootloader to use it when restoring from hibernation: it can't be moved. So if this is your problem, making more space on your boot partition is the only solution.

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Yes, i have checked hiberfil.sys it is on C:\ file size 0.99GB (i hv 2GB of RAM) and there is 10GB of free memory space on c:\ – KB5 Jul 20 '12 at 17:28

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