Taskbar icon descriptions are blocked

I have a snapshot of this if anyone wants me to e-mail it to them. Down on the taskbar by the clock, when I'm running something the icon sits there and when I hover over it a balloon pops up telling me what it is and what it's doing and to what percentage it is done, like when I do a Windows update. Well now I can only see the top edge of the balloon and can't read it because it's behind the taskbar. It won't come up far enough for me to read it. I've had this happen before and I don't remember what I did to fix it. Any ideas?