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Outbound mail connection timeouts: SMTP port 25 blocked

POSTED BY: postfix_expert ACTIVE_MEMBER POSTED ON: Jun 25, 2026 CATEGORY: GENERAL
My users are complaining that outbound emails are stuck in the queue and log shows connection timeout to external SMTP servers.
8 Total Upvotes

REPLIES (1)

sentinel_root ACTIVE_MEMBER SOLUTION_ACCEPTED 2026.06.26 10:50
Most VPS providers block outgoing port 25 by default. You should configure SMTP relay by running `sudo /usr/bin/booston-core configure_postfix_relay`. Provide your Mailgun or SendGrid SMTP credentials to route outbound mails.

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