For a number of years whenever I travel overseas or outside my ISP access area, I prefer to use my email client for receiving and sending emails ... all my contact information and historical material is right there on the laptop ... rather than logging on to any 'real time' web-based service.

In order to overcome the dreaded open relay problem for sending emails, I use GMail as my SMTP server, and this has worked just fine whether using a wifi hot spot or hotel/motel cable connection.

However, on a recent trip to Australia, where I was using a Vodafone T-stick for 3G mobile broadband, sometimes an email would go out as expected, but quite randomly it would fail with an error message window popping up asking me to enter my Username and Password for my GMail account ... this would persist regardless of the information already being displayed in the fields, or my correctly re-entering such. Sometimes this would still happen when trying later in the day, yet many times by the next morning all would be ok and emails would be sent with no problems at all.

Can anyone offer possible explanations as to what may be happening to cause this?

R.