Hi- Well, I have looked all over and cannot even find anything on a symptom like your computer has. Hang on, perhaps someone will recognize the flashing download box problem and be able to help. Keep trying to get the StartupList posted...will help us a great deal. Post the entire logfile it gives you if you can ever get it downloaded....perhaps, put it on a floppy and install it on the problem computer, and post the results that way.
Have a few questions:
1. Do any error or other messages appear when this happens?
2. Do you mean the whole box flashes...or, is it the icon down in the taskbar, in dark blue?
3. Virus scanned lately? Anything found, or quarantined?