IMAP timing out in Apple Mail in Big Sur

If your folders on the server side are empty but they contain email on the client side (mac), then this is probably due to a setting of the account to delete fetched email after x days. Yu can change that by right click on the account and then "Edit account...". If you can get new email from the server then it seems it works ok. There is no problem with Big Sur to connect with IMAP, this is a very simple and basic task for Apple to fail. The problem resides always on third party software that is not fully compatible yet with Big Sur. Apple is focusing on security and on keeping even the most tech-ignorant user safe by default and this causes a lot of trouble to software developers which, eventually, they overcome. If one claims he doesn't have third party apps or network filters, then most likely he is not aware of its existence or is not using the native mail app. Of course exceptions do occur, as always.

I also had problems after upgrading to OS Big Sur from Catalina. Initially a problem as cPanel configurations for domain email accounts did not make a compatible interface for an auto configuration. This appears to have been a cPanel problem. In any event, under Big Sur the Mail app does not take IMAP configurations as in will not save new entries or values, returns to "Automatically manage connection settings", does not offer the settings and protocols that email servers provide such as IMAP4 with port 993 rather than IMAP3 with port 995 and will not connect with an updated password, etc.

Why not just log in to gmail.com in a safari window and leave the connection open that way

I've been experiencing the same issue and it seems it is bigger than just Apple Mail. Since upgrading to Big Sur I have lost the ability to authenticate to any IMAP server with any email client. So far I've tried with Apple Mail, Spark ancd Thunderbird and all reported some form of connection issues. Curiously, Thunderbird also gave me a warning that my IMAP server was not using SSL when it very clearly is and has been. Like you, I am not having the same issue connecting through other devices connected to the same iCloud account (and therefore using the same email account settings). I'm stuck using my iPhone and webmail (ugh) to check my email until this gets resolved.

@syquest - Thanks for confirming that. I use Little Snitch and just updated my license to v5 on Saturday. I had a feeling these two are related but when I tried disabling the network filter through the Little Snitch menu option last night it completely disabled my network connection as if my WiFi went down and I gave up pretty quickly as it was late and I was getting frustrated. Looks like I have a test to do when I get home.

Thanks & cheers.

There is definitely a lot more problems to Apple Mail.

I also cannot get my Google SMTP to work. Used to work for years before the update....

Turning off Little Snitch is also not a solution. APPLE APPLE what is wrong?

Not directly related to BigSur, same problems arised some days ago with all imap accounts (in particular gmail) with Catalina too. Somehow, this timeout / data quote full problem has been solved up to today, although downloading from imap server now slower.

I'm having this issue too.

• Upgraded to Big Sur a few days ago
• Can receive all emails via Apple Mail
• Can't send any emails from Apple Mail
• Everything works fine if I go to my mail via GoDaddy's Workspace portal

I've been on the phone with GoDaddy three times today. I'm pretty sure it's not on their side. I've been on Apple chat for the past two hours trying to trouble shoot things. Nothing. I don't have anything fancy installed like Avast or Little Snitch (not sure what that is, but maybe I should look into it.)

Apple doesn't seem to know. They keep wanting to blame it on the provider, but it's not the GoDaddy side if email works 100% through their portal.

AND I can't send emails from my any of the desktops in the house, or iphones.

PLEASE Apple, figure this out and post an answer.

Hi all, I'm getting this problem and not running little snitch or Avast (or any other anti virus).

The connection to IMAP servers (for hotmail.com and iCloud accounts) times out for me but oddly, its fine when my wife is logged in as using her log in and connects to her hotmail.co.uk account???

email working fine on iPhones, iPads etc.

any suggestions please?

(MBP 2016 running Big Sur 11.0.1)

quick update - I run Microsoft outlook on my Mac (for work email account) but thought I'd try adding the hotmail account to that and it added and connected first time.

Would much rather have the hotmail account back onto apple mail (to keep separate from work!) and to get the iCloud emails connecting again in apple mail too! any help would be appreciated!

cheers

@amackey3: Thank you. This may have fixed my problem with Gmail smtp. I'll know better after my next reboot. Meanwhile, I can send via Gmail using Mail and Mimestream even with Bitdefender re-enabled.

Sounds similar to my problem. Since updating my iMac to Big Sur, I am not receiving all my emails. I get them on my Galaxy S20 ok and it's a good job I am. I need a GMAIL UK contact. Another human being I can actually talk to about this. Someone to talk me through my settings.

I am so tempted to sack Google right now.

Really, will there be any solution for that by Apple or not? I tried everything, but the synching still does not work. The connection between smtp and imap servers are ok. The AVG is deleted and I do not find any hidden AVG files. What else I can do?

Thank you. I already deleted AVG, and there is no other such "thing" on the mac. Again disabled the built-in firewall. What I recognized, that all my folders are "on the server", but there are folders which on my mac includes all the mails, but "on the server" these folders are empty. I tought it seems like before a "specific date" the mails are not synchronized, but after I realized, that there is not such a "rule". So my folders on the "server" are randomly empty. No idea, what to do. Luckily the fresh mails are synchronized.

I have the same problems like many others here. Some Mails (Smtp) are working fine and some not. But i don't have a network filter, there is blocking nothing but is not working also... i'm sure that the Big Sure causes all this problems. With Catalina everything was working fine with the Mails...I'm trying out what i can do.