I am still trying to figure out why my original reply got so thoroughly blocked by, I think, Debian's spam filters. So here is the original reply, with the acronyms replaced by wikipedia links. (For coherent reading, replace the wikipedia links with teh relevant acronyms)
On Friday 09 September 2016 16:02:42 mudongliang wrote: > Dear all, > > recently I suddenly failed to update my gmail account in > icedove. When I tried to get messages from gmail account in icedove, it > poped up one window : "Failled to connect server x...@gmail.com". There > is no error for my other email, for example, hotmail, outlook. > > How could I solve this problem? Look at the https://en.wikipedia.org/wiki/Simple_Mail_Transfer_Protocol or https://en.wikipedia.org/wiki/Internet_Message_Access_Protocol server settings. It looks as though something has gone wrong with the gmail settings. It would help if you were to say which gmail server you are having problems with, and what settings you are using. Lisi