
Make sure the Balanced Power plan is activated.Go to Power Options (Type Power options on the start screen & Click on the search result ).Type restore all your power schemes to the default Windows State.But, some times, due to Reset Power settings Windows 8.1 has been a major update for Windows 8 and has brought a lot of features to the initial Windows 8 release.

After reading this post you will be able to fix an issue with your Windows PC, where, on upgrading to Windows 8.1 from Windows 8, you are unable to put your computer to a sleep power state.
