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I'm running Windows 7 Ultimate as a developer box. When it starts, if I don't run any program, browser or app, it goes to sleep without any problem, but, when I start working on it, there's a moment when it starts getting awake forever. Even the monitor is on forever, it is never turned off. However, the sleep button works immediately.

I tried then

powercfg /energy

and I got this message

The Power Efficiency Diagnostic library (energy.dll) could not be loaded.

I searched for that dll and found it in C:\Windows\winsxs\amd64_microsoft-windows-energyefficiencywizard_31bf3856ad364e35_6.1.7600.16385_none_74c5223f50a58045 folder.

I tried also

powercfg /requests

and got this weird result




I couldn't determine yet the culprit of this, I had a similar problem with chrome some time ago but when I closed Chrome everything came back to normal, now it's not the case.

I'm using Microsoft Security Essentials as Antivirus and it's updated regularly by the way.

I can't find anything related on the internet, at least in Spanish or English which are the languages I can read. any ideas?

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up vote 1 down vote accepted

Try starting the command prompt as administrator and run powercfg in that window.

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I'm getting the same error, even when running as Administrator. There must be another cause. – Adrian McCarthy Jul 9 '13 at 16:15

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