Resolved Email is being deferred 4.3.2

[silvermarbles_ltd]

Server operating system version

CentOS Linux 7.9.2009 (Core)

Plesk version and microupdate number

Plesk Obsidian 18.0.67 Update #3 Web Host Edition

Hello

All of sudden no email is being delivered or sent via my server. All emails are in the queue as deferred.
Error is 4.3.2 deferred (host 127.0.0.1[127.0.0.1] said: 421 4.3.2 Service shutting down, closing channel (in reply to RCPT TO command))
I have installed Plesk Email Security (paid monthly version) as I was reading some other threads had this installed to resolve a similar issue but nothing has changed.
Do I need to restart the service? If so, how and what is the best thing to get the service back up and running again please?
Thank you

 

[Sebahat.hadzhi]

Thank you for reporting the issue. It is a known bug identified with ID EXTPLESK-8784, our team is currently investing it. Please apply the workaround from this article:

https://support.plesk.com/hc/en-us/articles/30609832237591-Unable-to-receive-email-with-Plesk-Email-Security-extension-installed-connect-to-sql-unable-to-connect-to-DSN-DBI-mysql-database-emailsecurity-mysql-socket-var-run-mysqld-mysqld-sock

 

[silvermarbles_ltd]

Hello

I followed that article and it worked. All emails are being delivered now. Sending and receiving is working.
Thank you!
Will this problem happen again soon?

 

[Sebahat.hadzhi]

I am glad to hear the issue is sorted. The behavior shouldn't reoccur. Our team will officially announce the fix soon. You can monitor the change log here.

 

[Sebahat.hadzhi]

Just wanted to confirm that the fix is released in Plesk Email Security version 1.5.12-5258. Instructions on how to update the extension are present in the previously linked article.

 

[silvermarbles_ltd]

Thank you kindly. I will update the plugin.