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How can i activate reject_sender_login_mismatch

Rouven Matthies

New Pleskian
Hey guys,

sry for my bad english!

I use Plesk 11.5 on a Debian server with postfix &dovecot.

I want to avoid that users can send with other e-mailsendersaddresses.

That's all normaly with reject_sender_login_mismatch.

Can you tell me how I can make with Plesk?
When I enter "reject_sender_login_mismatch" in the "smtpd_sender_restrictions", I get error that the address does not belong to the SMTP user.

Do you have a solution?

regards

rouven
 
Your question is really not clear, however if you have a closed relay MTA set-up, then it means ONLY validated SMTP username / password are allowed to send out email!

You may however also need to enable SPF (Sender Policy Framework (SPF) is an email validation system designed to prevent email spam by detecting email spoofing, a common vulnerability, by verifying sender IP addresses.)
 
if the SMTP data are correct, no matter what is entered for a sender, it can also be a sender to be entered that does not exist on the server.
 
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