Yes, it may take several Restarts or even a Shutdown.

Next try SFC -SCANNOW Command to check for System file damage. You may need to run repairs several times.

If not then install SP1 with the standalone installer: Download: Windows 7 and Windows Server 2008 R2 Service Pack 1 (KB976932) - Microsoft Download Center - Download Details

I would also be working through the Troubleshooting Steps for Windows 7 to check for clues in the logs, utilizing System resources, doing all of the due diligence to assuring the OS is sound. If not the steps are there to get a perfect reinstall.