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Realtime Blackhole list (RBL) Question

My boss has a sympatico email account but for some odd reason, sympatico only allows your to send email (smtp) through outlook if your using your sympatico internet service. The problem is that my boss is now in Florida and far away from any sympatico service.

My colleague suggested we use a different SMTP server that we use for the company. The SMTP server is not an open relay but are we still risking being put on a RBL?
1 Solution
Typically ISP's allow their customers to send mail through the ISP's mail servers, regardless of the 'from' address of the message.

Your boss could try setting his outbound (SMTP) server to that ISP's outbound mail server (usually mail.isp.com or smtp.isp.com, but check with whatever ISP he is using).

The only drawback to this is if you (or sympatico in this case) has SPF (Sender Policy Framework) configured for the domain, mail servers can still reject the mail based on the fact that it was not originally delivered from a trusted sympatico mail server.

Alternatively, some ISP's also allow users to send mail via their mail servers from anywhere so long as the user is authenticated - you could query sympatico to see if they offer this service, and they would also be able to provide the relevant instructions on how to enable it from the client side.

I would not recommend using any server that relays mail from any source, as that mail server would typically be blacklisted very quickly.

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