It is 5.5.902
TO ALL THE KIND PEOPLE WHO HAVE BEEN HELPING ME WITH THIS ISSUE: i may have solved it. I had changed the security in GMail settings on the computer from http to https recently when Google noticed a suspicious (from Vietnam) IP address in the activity. I just changed it back to http and Voila! I was able to send a couple of messages from the phone! HOWEVER, I'm still puzzled by the fact that I got Send error messages BEFORE I went to https. But to all that have worked to help me THANK YOU 100 times over!!! If you can figure out the timing of the resolution, I'd love to know it, but perhaps I should be satisfied with what I've got.