Ever since I added an SSD, once in a while, gnome2 won't be able to load a random panel applet on login. (It was a dual-core system until the slow death of I/O interfaces on the motherboard finally consumed SATA, at which point I replaced it with a quad-core board.) That means that every now and again, I get an error similar to the following:
This OAFIID is actually relatively transparent. Sometimes, I get ones that look more like a UUID and I ask the dialog, "How does that give me any information?" There's not even any indication about what the error was. (It is floating around in ~/.xsession-errors, with the helpful indication that the child didn't return an error.)
Fortunately, the answer is always the same: Don't Delete. Things will most likely work next login.