□□□□□ windows xp startup error

When I start my fathers computer, an error message stating windows cannot find or run a, "□□□□□"file appears. It says if you want to find it, click start, search, etc... I have never seen anything like this before, so I have no clue where to begin. I searched the registry and found nothing, I have followed Greyknight17's anti-spyware tutorial, so I don't know if a HJT log first would be a quck and dirty way to find anything. I also have four updates for various MS Office programs that refuse to update. Any info is appreciated.

Sometimes when I'm working on a customers PC, I of course look at what's starting up in MSCONFIG and I see an entry that's just little square boxes like that.

I always DE-Select that item so it won't try to run.

Try that.

Click the START button, then click RUN, then type MSCONFIG into the text box and press Enter. When the window opens, click the Startup tab.
There will be a list of all the programs set to start at bootup.
Uncheck all the items that don't need to be running all the time.

Doc