Hi all,
Today as I was using my Thunderbird, all of a sudden, my webmail-yahoo account stopped working, complaining negative vibes. I had to remove webmail on my office computer for the same reason , switching to IMAP.
Fortunately this time I know what I had done. I had just installed Google Task Sync extension. It required me to turn on cookie support. Negative vibes appeared right after enabling cookie support,
So for those who with the same problem, I suggest you check out your cookie settings. If it is on, then try to turn it off, or block
yahoo.com,
mail.yahoo.com to see if this helps.
ywliu