mail.ru (the most used Russian mail provider) and vk.com (a russian messenger app) recently decided to cooperate closely. On Linux desktop trying to use webmail (using firefox) to reach mail.ru, I have to solve a captcha (put to me by vk.com) everytime (extremely difficult, since there is a slider to move until you see distinct Russian words.Btw. I know Russian, but I struggle). Installing it in thunderbird using imap.mail.ru and smtp. mail.ru and setting the TLS and port numbers, this is what all sites tell you to do when you search, absolutely doesn't work, even if you set your vk identity (which I know) as a password instead of the mail password or the vk.com password. Before this mail.ru/vk.com cooperation, I could easily use mail.ru just via imap etc., using my normal password. This is definitely gone. On android however, it's easy: There is a mail.ru app in the playstore, working very well. I don't want to use mail.ru on android, since typing on android is cumbersome.

Firewall: Access Firewall - it might be the default on computer or controlled by an Anti-Virus prgram. Set up Thunderbird program as 'allowed' so nothing gets blocked. Confirm Thunderbird is set up as allowed program.

VPN: Check computer for a VPN. Some Anti-Virus products now offer a VPN and I have come across some peopl who did not realise one had been enabled. Switch off VPN (or create split tunnelling and set it up for Thunderbird to use). Many servers do not like VPN as it atempts to hide your IP address, so server decides you might be hacker so it auto blocks access. Confirm VPN is switched off

Server Settings: IMAP

• Incoming server name: imap.mail.ru
• Port: 993
• Connection Security: SSL/TLS
• Authentication Method: Normal Password
• Username : full email address
• Password: generated app password

SMTP Outgoing

• server name: smtp.mail.ru
• If using Port: 465
• then use Connection Security: SSL/TLS
• If using Port: 587
• then use Connection Security: STARTTLS
• Authentication Method: Normal Password
• Username : full email address
• Password: generated app password

Not sure what you meant regarding password, but I'm assuming it's the following to set up a 2FA password. I located this info from a bitrecover website: https://www.bitrecover.com/imap-settings/mail-ru-email/

Logon to webmail account via browser You need to simply Login into the account for email address. Go to 'Password & Security' then Click on 'Two Factor Authentication'. After that 'Enable' Two Factor Authentication.

Then you need to Add app for Third Party Access of your Email Account. After choosing Thunderbird, you should get a new special password which you need to copy and use in Thunderbird, so when it asks for password you enter that app password.