# SMTP issue, could not connect to SMTP host error

**URL:** <https://forum.inductiveautomation.com/t/smtp-issue-could-not-connect-to-smtp-host-error/94051>\
**Category:** Ignition\
**Created:** [August 1, 2024, 3:35pm UTC](https://forum.inductiveautomation.com/t/smtp-issue-could-not-connect-to-smtp-host-error/94051 "2024-08-01T15:35:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Zach\_Larson](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/zach_larson/32/54388_2.png) [@Zach\_Larson](https://forum.inductiveautomation.com/u/Zach_Larson)\
**Post date:** [August 1, 2024, 3:35pm UTC](https://forum.inductiveautomation.com/t/smtp-issue-could-not-connect-to-smtp-host-error/94051/1 "2024-08-01T15:35:00Z")

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My error says "Could not connect to SMTP host:..." when I run a test.

I contacted my IT, and they said the SMTP host is listening.  
I have 3 gateways testing with the same settings working and one not working.

Is there a bug out there that is know that might be the issue on the Ignition side?  
Or do I ask for another SMTP to test against to see if it is the gateway vs the SMTP host?

What is recommended?

I appreciate the help.

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**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [August 1, 2024, 3:38pm UTC](https://forum.inductiveautomation.com/t/smtp-issue-could-not-connect-to-smtp-host-error/94051/2 "2024-08-01T15:38:03Z")

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The target host is probably running a blacklist, like `fail2ban`. If you tested with incorrect settings a few times, that might have triggered. Have your IT double check such things for the failing gateway's IP address.

Also check that there is actually a network path from that gateway to the SMTP server (`traceroute`).

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<div class="post-metadata">

**Author:** ![Zach\_Larson](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/zach_larson/32/54388_2.png) [@Zach\_Larson](https://forum.inductiveautomation.com/u/Zach_Larson)\
**Post date:** [August 2, 2024, 12:29pm UTC](https://forum.inductiveautomation.com/t/smtp-issue-could-not-connect-to-smtp-host-error/94051/3 "2024-08-02T12:29:49Z")

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There was an authorization list for an app server that needed to be given permissions.

Thanks again for the help @pturmel