Strange, disembodied error message

Error message: "Username and password do not match. You provided xyz@comcast.net. Please enter your full email address (including @domain.com). "

That error message shows up in the middle of my desktop behind Windows. It is my correct email address. I have no idea what it's supposed to pertain to.

Can anyone shed any light? How do I get rid of it?

 

How are you getting your mail. Straight from the server or to you PC from a e-mail program loaded on your PC? Have you checked for a virus or Malware/Spyware?

 

Outlook error message

Thank you for responding, MrBill. I use Outlook, and now that you ask, I do think I always see the error message after I close an Outlook window. I have Avast Internet Security and Spybot Search and Destroy, as well, and keep them current.

 

Extra account

Thank you, TonyT. I did check, and I don't see any extra account. Could it be somewhere besides in Outlook?

 

Look in your outbox and see if you have a mail that is in there. If so and you don't care about it, delete it and see what happens when you try to close Outlook.

 

Still getting error message

I've deleted anything that looks unnecessary or suspicious in my Outlook folder and still get that error message. I'd sure appreciate any more ideas.