Re: Error message I don't understand (RESOLVED)

Well, the problem is resolved, but unfortunately I can't give
any further information about the cause, because it resolved
spontaneously.

I decided that the next thing I should do is put the problem 
to our university email and network people to see if they could 
find the answer.  For various reasons I've put off doing that 
until today.  But when I sat down just now to compose an email 
to them, I found that the problem had vanished.  Everything 
works just fine, as it did prior to December 27th.

Both Getmail and Thunderbird have spontaneously begun working 
again, so no further testing can be done or is needed.

Thank you all who have responded to my request for help.

Donald MacDougall