Hi,
- Did you make any changes to the computer prior to this issue?
This issue might occur if the related system files are either corrupted or missing.
Method 1: Unplug all external devices and restart the computer to check if this helps.
Method 2: Let us try using the Last Known Good Configuration. It's a Windows startup option that uses the most recent system settings that worked correctly.
Using Last Known Good Configuration: http://windows.microsoft.com/en-US/windows7/Using-Last-Known-Good-Configuration
Method 3: I would suggest you to access the System Recovery Options screen and try system restore. You can use the restore points to return Windows 7 to a previous state when
your computer was functioning correctly.
What are the system recovery options in Windows 7?:
http://windows.microsoft.com/en-IN/windows7/What-are-the-system-recovery-options-in-Windows-7
Important: System Restore will not revert any of the non-system files like documents, email, music, etc. to a previous state. These types files are completely unaffected by System
Restore. If your intention with this tool was to recover a deleted non-system file, try using a file recovery program instead of System Restore.
Reply with the status of the issue and we will be glad to offer our assistance.