What is Rundll32.exe?

General Info
File Name     Rundll32.exe
Process Name     Microsoft Rundll32
File Location     C:|Windows|System32

Rundll32.exe is a system process which comes included with Windows. The official process name is Microsoft Rundll32. File sizes will differ from computer to computer but documented file sizes are 33,280 bytes (87% of all occurrence), 31,744 bytes and 44,544 bytes.. Rundll32.exe should not be disabled or removed because it's an essential file required by your computer's Windows Operating system. But Rundll32.exe may be damaged and corrupt causing errors, high CPU usage and slow computer performance.

To Fix Rundll32.exe

Download exefix from here and run it it will fix the problem