DOS window

  Every now and then, I have a DOS window popup, with some writing in it.  Before my old eyes can focus on the writing, the popup goes away.  I don't think it's malware, because all my scans come up clean.  I really think its one of my programs "Calling Home" for instructions but I don't know for sure.  I've looked in the Event Viewer, but nothing is showing up there.  Is there a way to see what is going on?  No problem that I know of, but I'm nosy..