rundll32.exe won't end when shutting down

For the past 2 to 3 weeks, when I try to shut down the PC the rundll32.exe program will not end. I have to manually click the "end now" button to terminate it and shut down the PC. I have checked the processes and I only have one running. I have performed scans with Avira, Malwarebytes and SuperAntispyware with zero detections.
It appears this is creating another problem since this started after the rundll32.exe error appeared. When I click on a link to open a new window, the new window freezes and I have to "end the task" and then both windows close. Very frustrating......please help! Thanks!

 

Sorry...my mistake....saying it is a rundll32.exe "error" is probably not the correct terminology. When I try to shut the PC down, the rundll32.exe program will not end automatically. A box pops up and advises that the program will not end and I have to manually click "end the program" so the PC will shut down. The only other option is to cancel out of the box and return to the desktop. Whatever this rundll32.exe is doing it will not allow the PC to shut down without me performing the step mentioned above. The problem with the window not responding, started after the issue (described above) with rundll32.exe started. Please advise. Thanks a bunch!