Is your machine running ok otherwise? Have you changed ....say the log in background ? Why were you running chkdsk and sfc/scannow in the first place? I ask because changing the background and/or start orbs etc. can sometimes cause the "corrupted files" thing you mentioned. I have went through this myself. My machine run's perfectly so.......
Try SFC -SCANNOW Run in Command Prompt at Boot using the DVD or Repair CD.
If this fails after 3 passes, find a Win7 SP1 Installation DVD for your version and run a Repair Install.
It's obvious you are interesting in troubleshooting your computer so I'd also run through these troubleshooting steps to see if anything else comes up.
@ indian my computer runs ok
@ GregI have not noticed any problems and SFC found no integrity violations...so should I repair install anyways?
I would not, unless you want to try a Repair Install to experience it.
Instead at your leisure I would work through the other troubleshooting steps to get a full PC checkup which may come across another or related problem, or give you clean bill of health.
Or do nothing at all and watch performance carefully.
Quote