Mac Mail problems
I have been having problems with Mac Mail for a while.
I have two email accounts with my ISP. One works fine, the other receives emails but won't send. I have checked the settings based on the ISP's guide" and they seem to be OK, though they are slightly different in each account (port and authentication).
When I try to send an email from the "bad" account, I get an error box saying (among other things): "Cannot send message using the server <my email address>. ..... The server response was: relay not permitted, authentication required".
So I tried to change the bad email port and authentication to be exactly the same as the working account, and when I tried to save the settings I got this error message: "A SMTP account already exists. Only a single SMTP account is allowed to be saved."
Is someone able to explain to me what these error messages might mean please"? Why can't I save changed settings on one of my Mac Mail accounts?
Please help, this problem is driving me crazy. I don't want to have to move to third party Mail software, but this is unacceptable.
Is it likely that Big Sur might have de-bugged Mail software?
Thanks for any help..