Over the last few months, I have used IE, Firefox, Chrome and Safari to see if any of them behaves any differently than any other.  Even though I do have some issues with Firefox, it looks like I will stay with that now.  And, that is what was running today when I got that message again.  I almost think that I got that message at least once with each of them.  I am presently using Thunderbird for email but I am going to look for something else.