end program now box

Hi, I need some help.
Whenever I go to log off my screen name I receive one of those "end program
now" box that comes up for just a second and then goes away(i never have to
click on the end now option, it just seems to do it automatically) When it
comes up for those few seconds, I can glimpse the title at the top of the box
and it says "windows forms parking window" Even though it doesn't seem to be
affecting my system, its irritating and seems to take longer to long off than
usual.
Anyone know what this is?
Thanks in advance.
Darlene
.