As protonmail user I came across Proton Bridge and thought lets give it a try. After installing it and making an account in thunderbird everything went fine, except for one thing. I cannot send emails using thunderbird, but I do receive new emails in the client. When I try to send something I do get the following error message: Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) 127.0.0.1 was lost in the middle of the transaction. Try again. (see pictures) The SMTP settings are equal to what Protonmail describes on the website how they should be, but see pictures for the settings I use. Maybe also good to mention. I did see someone with the same problem and the solution for that person was turning off the antivirus. So i tried that but that did not solve it for me. Using Emsisoft antivirus. Please can you help?