Posted 01 March 2017 - 11:24 AM
Were I you I would just delete the accounts in Thunderbird and re-create them. With IMAP access all your messages are stored on the server so you just get them all back when the account is created anew again.
I really have no idea why this would occur suddenly. I've got Gmail accounts setup in MS-Outlook 2010, Thunderbird, WLM 2012, & Opera Mail and they've been and continue to be working fine in all of them. All I can imagine is that "something burped" in Thunderbird itself that's causing the issue. Removing the account and re-creating it should at least tell you whether the problem persists.
Brian AKA Bri the Tech Guy (website in my user profile) - Windows 10 Home, 64-Bit, Version 1803, Build 17134
In a modern society where everyone thinks their opinion deserves to be heard nothing annoys me more than individuals who mistake their personal preferences for fact.
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