Gmail Issues On Just One Computer

Hello,

This might not seem like a question normally asked here, but I have a user who is having an annoying issue with Gmail.

Whenever she attempts to do anything: Send A Message, Show All Mail, Read a Message, a message appears at the top of the screen: "Invalid Search" or "Invalid Search Query".  Even though the error is displayed, the page results are normal.  For example, you still see All Mail. These symptoms do not appear all of the time, but they do frequently.

These issues only occur on her work computer, at home and on other systems, this never happens so I think it is safe to rule out a problem with her account.  I suspected an issue with Internet Explorer so I installed Firefox.  The same problem occurs there.

The computer is a brand new Dell, and has done this since it was taken out of the box last week.  I've run all Windows Updates but it did not change the problem.  Can anyone think of any reason why this would be happening on just one machine.  

I've googled this issue and have not come up with similar situations.  I do not believe the computer is infected with any type of Malware, as I've scanned with a variety of apps, all of which have come up clean.  

There is no google software installed on the machine, and no toolbars, plugins, etc.

Thanks for any advice.