Click start, go to "Run" and type "msconfig",without the quotes, the go to the tab labeled "startup" and disable everything and if it goes away then re-enable everything one at a time until it comes back, then you know it was the last thing you re-enabled that was causing it. Check all the boxes again except for the problem one. Usually works for me as a last resort. If you know the name of what's causing it then just disable that if it's in the list somewhere.