Our neighbor had this problem. After their PC came up the windows Icons and Start bar would flash for a second or two and then disappear. They bought and returned 3 different HP machines with XP on them and they all did the same thing. At first we thought it was the norton system check. We removed all Norton and Symantec programs and installed AVG, Ad-Aware and Spybot (all free). That didn't clear anything up. After asking a few questions we realized that the problems started when an older SBC/Yahoo DSL installation disk was used to set up internet access. Once all SBC Yahoo products were removed from the machine with the ADD/Remove function of the Control Panel the ICONS and Start Bar returned. The older version of the SBC Yahoo products seemed to have somehow blocked the running of EXPLORER.exe which is vital for Windows to run properly. The icons and start bar worked in Safe mode and they worked in diagnostic mode. That told us it was something in the start up which contained all the Yahoo/SBC. Not that Yahoo/SBC is evil. The older disk just did not jive with the newer machine's version of XP.

so many times I will get a problem from an end user fix it only to have it show up a day or 2 later with the problem magically restored they are pissed off and can't remember doing anything special ... did you install or update anything recently ? I ask . Oh yes I ... they state is that what you did last week too ? (rather sheepishly they state)yes ... but why? well there is your problem (doctor it hurts when I do this ... then don't do that) oh but I need that program then find one that work's for your machine and throw away that install disk