How to Repair Rundll32.EXE Errors

1. Press 'Win' and 'R' on your keyboard. The 'Win' key sits next to your 'Alt' key with a Windows icon.
2. Type 'cmd' in the box and click 'OK.'
3. Put your Windows CD/DVD in your CD/DVD drive.
4. Type the following command in the command prompt: expand d:\i386\rundll32.ex_ c:\windows\system32\rundll32.exe. Replace 'd' with your DVD/CD drive letter and 'c' with your system hard drive's letter. Replace also 'windows' with the proper Windows folder. On Windows 95/98/XP/Vista/7, the folder name remains 'Windows.' For other systems, replace 'Windows' with 'WinNT.'