IMAP timing out in Apple Mail in Big Sur

Have heard any word when this will be corrected. I lost all my Bellsouth.net email. It's not in my iCloud Backups since I upgraded in November 2020. I truly wish all Microsoft Office Business & Home, etc. software should have been checked since Microsoft was working with Apple & this was on my very new 16" MacBook Pro, 1 day old iPhone Pro Max.

Thank you for your reply. Happy 2021 stay safe and my this new year bring you, your family & friends much happiness.

Same problem with BigSur Mail on my new 2020 iMac. Did anybody come up with a solution other than de-installing anti-virus (and other network filters)? IDK what sucks more. Having to restart router/iMac every time you want to check for new eMails, or having paid for (but being unable to use) network filtering apps?

I feel you pain I lost all my bellsouth email and my paid Microsoft Office Outlook will not open, but all other Office works. It’s really a shame that this was never corrected and I have been dealing with this since the day Big Sur was released in November 2020. Not Beta. I never install Beta anything. Plus my protection is Malwarebytes paid. That Apple told me to get and stop my Norton 360. I have been using my Paid Malwarebytes Premium fir years. All of this happened on the bay day Big Sur was released and it’s all on my new MacBook Pro 16”, iPhone 12 Pro Max, iPhone 12 Mini. So I know your pain. It’s a pain in.....

I'm having the exact same issue in 2021. Was this ever resolved? I have been on the phone for hours with GoDaddy reps and Apple reps, to no avail. Has anyone been able to figure this out or is it time to utilize a new email provider?

Thanks!

Same issue with Xfinity Comcast email.

thanks but as noted above I'm not running ANY antivirus software

I'm experiencing the same issues, BUT I don't have any antivirus software.

So, what is wrong?

Thank you, after days of frustrating trying everything, finally this works!!!!!

Nothing has changed. But thanks...

OK, so there is an update today for Big Sur. Installed it, but nothing has changed...ridicuolus!

Tried to turn off firewall. Nothing happened. I am really desperate...might be the macbook 12" the problem?

Thank you for your reply. I have Malwarebytes for Mac paid subscription for several years.

Happy 2021 stay safe.

Same problem here:

IMAP for different accounts (own servers and gmail) does not work anymore since upgrade to Big Sur. Used to work on Catalina. Nothing has changed, besides upgrading to Big Sur.

Works on iPhone, iPad, Apple Watch, though. But not on my Macbook pro. Tried different things up to a new "install" of an email account. Nothing helps. Very annoying. Can't work anymore.

So to follow-up, I can confirm that the issue is 100% related to applications with a network filter.

As mentioned above, I am running Little Snitch (v 5.0.2). Attempting to disable the network filter using the menu option killed my networking until I restarted; no amount of attempting to turn it back on again restored my network connections.

After rebooting and confirming that networking was re-enabled, I completely uninstalled Little Snitch (the instructions in their help docs have not been updated for 5.0.2 - deleting requires dragging the Little Snitch app bundle to the trash and confirming the removal of the network filter extension from the pop-up dialog) and rebooted. Immediately after rebooting, I opened up Apple Mail and it worked again and started downloading the backlog of email for the past two-plus days.

I'm currently submitting a bug report with Objective Development, the makers of Little Snitch, although as mentioned above it appears this affects any application with a network filtering extension in Big Sur.