rundll32.exe is out of control!
Have you ever experienced sluggish computer performance and checked your task manager (taskmgr.exe) so see if it was a service or process that was out of control or not running? In you search you find, to your dismay, you see that you have about a thousand rundll32.exe processes open and now it's sapping all of your CPU power and all of your RAM! (In windows vista, you're only supposed to have two rundll32.exe running at any given time and usually the same for XP). You have no idea where the process is being started from and you want to find out and see if it is a virus or not. If you're running XP then I have some bad new for you. To my knowledge, you cannot see the command line of the source file that's causing all of this drama; however, if you have vista then you can simply go to the view tab and pick the select columns icon. Scroll down to the bottom and select the command line option check box.
When this check box is selected, you will be able to see the command line version of the specific location of that process and what rundll32.exe is actually executive (exe).
If you do have this problem and you trace the problem back to internet explorer, then you need to install ie to the latest edition or you may need to reinstall completely. If, however, your problem is not traced back to ie then do a Google Search on that particular process in question (be sure to add the file extension e.g. taskmgr.exe, system.sys, etc) and you can review opinions through a google search.