In some cases, when you open the lid of a laptop running Windows Vista, Windows 7 or Windows Server 2008, which you had put to sleep sometime back, it may not resume correctly.
The computer gets stuck in resuming windows and displays a blank screen with mouse pointer and will not resume until you press some keys etc. This problem is mainly seen in : Windows Vista SP1 , Windows Server 2008, Windows Server 2008 R2, and Windows 7.
This is a known Windows bug and a hotfix has been provided by the Microsoft for the same.
NOTE: You should only use the hotfix only if you observe this problem, because this hotfix is still under testing.
You will need to request for the hotfix by Microsoft at the below page to get one for your impacted computer.