Symptoms
Assume that you connect an AC power source to a computer that is running Windows 8.1, Windows RT 8.1, or Windows Server 2012 R2. You disconnect the AC power source. In this situation, the computer sometimes enters hibernation immediately instead of turning on the display to indicate that the computer is now using battery power.
Resolution
To resolve this issue, install update rollup 2975719. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
2975719 August 2014 update rollup for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More Information
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates