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My ISP blocks SMTP on port 25 - what can I do?

An increasing number of ISP's and firewall configurations block outgoing mail / SMTP connections on port 25 (the default port for SMTP) - this is mainly done to try and stop spam going out through their networks.

The issue is this can cause problems when you 'need' to bypass their servers (their servers may be unreliable or overly restrictive) or if they block port 25 and do not provide SMTP servers themselves!

AuthSMTP can help solve this problem - we operate AuthSMTP SMTP servers on the following ports: 23, 25, 26, 2525 - we recommend (where possible) you use SMTP port: 2525

If you do not already have an AuthSMTP account click here or review the features, benefits and low cost.

For details of how to setup your email program to use an AuthSMTP with alternate SMTP ports click here.

If that does not work (or you email program does not support changing the SMTP port) contact your system administrator / ISP about allowing outbound connections to our servers on ports: 23, 25 or 2525.

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