This happened once with AOL, and now it's my Sony/Ericsson phone suite.
I click on the icon to open the program and the program appears on my
taskbar, but I can't see it. If I right click on the taskbar and alternate
between minimize and maximize, it looks like the program is opening in a
window out of view at the bottom of my screen.
When this happened with AOL, someone suggested right clicking the taskbar
and changing the tiling of the windows. This worked fine, but when I try it
for my Sony program, tile vertically and horozontally are greyed out. I've
already tried changing my screen resolution and restarting the computer.
BTW-- if this helps, on both occasions my wife had been playing a lot of
online Java games when this happened.