Our mail functionality is not a full-fledged email client and does not attempt to replace it. When you click on the "Send" button, the email is added to the queue for sending to your server.
If you have set many tasks to send / receive letters (letter size also matters), then letters can form delays in the queue.
Processing of messages can occur with a delay. We constantly work on the section "Mail" and try to improve it.
Total attempts to send 5 (If at the first attempt the letter was not sent, then a delay is established and after a while we try to send the letter again).
If the letter is long hanging in the queue for sending, try:
Refresh the page;
Check the status of the message in the "Mail" - "Outbox" (Perhaps there it is already with an error);
Perhaps you changed the password, and the box stopped synchronizing. Try to update the password. More you can read here.
We after sending, we can get and other errors except "In the queue." We receive the error data from your mail server. More details on errors can be read here.
In case of difficulties, please write to the technical support chat. We will help you in this matter (the picture on the upper left is the blue button to ask for support).