Issue All Emails being deferred

[Gripfuel]

Server operating system version

Ubuntu 22.04.5 LTS

Plesk version and microupdate number

Version 18.0.69 Update #4

Plesk Obsidian 18.0.69
Lightsail VPS
Stock install, with licence - no extensions added

I have added 3 domains and enabled webmail on all 3. Websites all resolve fine. Incoming mail arrives fine

However, anything trying to be sent from them is not being delivered. Looking at the mail queue, everything is showing as 'deferred' with status 'connection time out'.;

4.4.1 deferred (connect to mx01.mail.icloud.com[17.57.152.5]:25: Connection timed out)

Annoyingly, there is no indication within webmail that there has been a delay or any other issue, so this has gone under the radar until someone asked why their email hadn't been received.

All other threads point to a security extension, which I haven't added. Aside from adding the domains, the install is about as 'clean' as it could be.

Anything else I can try? I have already rebooted the server

 

[Kaspar]

Usually this is an indication that port 25 is blocked, which is likely a restriction your provider has put up. Contact them to see if port is 25 blocked and what options they offer to open the port.

 

[Gripfuel]

Usually this is an indication that port 25 is blocked, which is likely a restriction your provider has put up. Contact them to see if port is 25 blocked and what options they offer to open the port.

Sorry, should have noted that - I have already checked that port is unblocked on Lightsail

 

[Kaspar]

Did you also submit a request to AWS for the removal of the 25 limitations as outlined in their knowledge base article?

 

[Gripfuel]

Did you also submit a request AWS for the removal of the 25 limitations as outlined in their knowledge base article?

I did not, I hadn't seen that - thank you for pointing me in that direction. I've submitted the request and will update here if that resolves once actioned.