Since yesterday keep getting unrecognised IMAP4 command when trying to access bt mail via thunderbird have checked all the setting reinstalled thunderbird etc it seems when accessing gmail via thunderbird no problem contacted bt said not them and to contact thunderbird ERM!...did some testing and this is my scenario... it seems to throw the error when you first click on any folder eg TRASH OR SENT then second time you click on folder it may not throw error HOWEVER when you send an email it throws the error unreqognised imap4 command about the sent folder and as a result you dont get a saved copy which is bloody annoying as you dont know if its sent or not and it seems gmail account dosnt seem to do it and it seems random sometimes it works ok then it will also ask for login again at random and BT say its not them …...funny how theve just revamped their email client to make it easy well it seems theve mucked it up and wont believe the customers once again
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I've been using Thunderbird for some time without problems. This morning it brings up an error message saying that the server cannot proceed with the Inbox, because of an unrecognized IMAP4 command. It seems to have stopped downloading outstanding messages. I sent myself a test message from another non-BT account to test this. It is set up as an IMAP account. I would be grateful for any help or advice to get my email client to work.
I get the same message since updating to TB 60.8.0 but everything seems to be working ok so I just ignore it.
Thanks for the reply. Yes, I was recently updated to TB 60.8.0. The message about the IMAP4 command still comes up but some messages are getting through.
I had the same problem with a customer running Thunderbird. Email was working OK until yesterday. Check you are using mail.btinternet.com for both IMAP & SMTP servers. My customer was using imap.btinernet.com. As soon as I changed it the unrecognised IMAP4 error stopped.
Thanks for that @Cloudscape. You're quite right TB does fill the server name as imap.btinternet.com for some strange reason but in my case changing that to mail.btinternet.com made no difference.
I think I've cleared the problem now but have to admit I find it odd bearing in mind what I did which was simply to go into Tools/Options/Advanced/Network & Disc Space, click connection settings, check that " Use System Proxy Settings" was selected (which it was) and then clicked OK. Why that should fix it when it was already selected I don't know but I've not had the problem at all since doing it yesterday
Sounds like a good idea. I did try re-installing TB 52 to see if it's a bug in version 60, but of course the first thing it did was to search for an update the second I launched it. Sticking it in the "one of those things bin" sounds good to me.
Thanks for the suggestions to check smtp server names and refresh network settings. I also checked the list of smtp servers (e.g. from tools-->account settings) and deleted several (probably invalid) servers left over from some old email accounts. The combination seems to have resolved the issue for me (touch wood).
(but why I have to create a specific account to comment on this forum when I'm already a BT customer is beyond me:-) )
Spoke too soon - after appearing to work for several restarts of Thunderbird, IMAP4 once more unrecognised.