Hi ,
I get an error message whenever I reboot, it is in a little 3x2 window and the text is as follows: Registry Data not found. I click the radio button to cancel and it sems there is no problem in that I am able to do whatever I had planned, programs seem to run okseem.
My operating system is XP home.Should I worry? 
There must be a problem with a program that’s running at startup. You can go to Start|Run, type msconfig and selectively disable items on the Startup menu to narrow down the cause of the problem. Alternately, run HijackThis and post the log here. It will show everything that’s running at startup.
I find Autoruns less intimidating than HijackThis, through simple things such as using icons, and titles rather than obscure codes. Of course, HijackThis is in the end more powerful, but it’s not something to be used without guidance.