Step 1Log in to Windows using an administrator account.
Step 2Uninstall or roll back any driver (especially if it’s a video driver) or software you may have installed just before the problem started. Reboot your system and see if the Rundll32 error message persists. If it doesn't, the problem has been resolved and you can skip the remaining steps.
Step 3Launch your anti-virus software and run a full system scan. Clean or quarantine any infected items found and then reboot your system. Run follow-up scans until the system comes up clean.
Step 4Log back in to your system (if necessary) with an administrator account.
Step 5Click Start, type “cmd” (without quotes) in the Search box and press “Enter.”
Step 6Type “sfc /scannow” and press “Enter.” Windows will scan all your system files (including Rundll32) and repair any damaged files. Reboot your computer when the scan is complete.
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