To resolve this problem in Windows Vista, run the powercfg -h on command at
a command prompt to enable the hibernate feature and the hybrid sleep
feature. To run this command, follow these steps:
1. Click Start, click All Programs, and then click Accessories.
2. Right-click Command Prompt, and then click Run as administrator. If you
are prompted for an administrator password or for confirmation, type the
password, or click Continue.
3. Type powercfg -h on, and then press ENTER.

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Mark L. Ferguson
.
> thanks for the reply idid use the disk clean tool about the same time as
> hibernate disapeared can i get it back? and do i need to worry as i did
[quoted text clipped - 10 lines]
>> > updates
>> > but cannot be sure that is the cause
marty - 22 May 2008 19:42 GMT
many thanks problem solved

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martyb
> To resolve this problem in Windows Vista, run the powercfg -h on command at
> a command prompt to enable the hibernate feature and the hybrid sleep
[quoted text clipped - 18 lines]
> >> > updates
> >> > but cannot be sure that is the cause