Intermittent email forwarding

[simes]

Dear support,

For some time I've experienced what appear to be intermittent email forwarding failures to my email @hetzel.co.uk. Failures (seem...) to be infrequent and senders didn't appear to be aware so I don't have NDRs from them. When emails have been resent I've usually received them but the originals have never arrived (not even been delayed). Recent examples have included emails from @crowdcube.com and @lucid-support.com.

More recently I've received an NDR to my own emails to @hetzel.co.uk - I'm not sure if this is related to the emails I've not received or not:

Redacted NDR as follows

===============
From: MAILER-DAEMON
Sent: 05 December 2025 13:41
To: ***@hetzel.co.uk <****@hetzel.co.uk>; ***@hetzel.co.uk <***@hetzel.co.uk>
Subject: Undeliverable: The European avocado season begins



Delivery has failed to these recipients or groups:

***@hetzel.co.uk
Your message couldn't be delivered. Try to send it again later. If the problem continues, please contact your email admin.

***@hetzel.co.uk
Your message couldn't be delivered. Try to send it again later. If the problem continues, please contact your email admin.





Diagnostic information for administrators:

Generating server: mxc03.zoneedit.com

***@hetzel.co.uk
Remote server returned '554 4.3.0 < #4.3.0 X-Postfix; unknown mail transport error>'

***@hetzel.co.uk
Remote server returned '554 4.3.0 < #4.3.0 X-Postfix; unknown mail transport error>'
...
...
===============

I can supply more details via private message.

Regards

--
Simon

 

[zeadmin]

Hello Simon,

I had our Tier 2 take a look at the issue and it seems Microsoft is blocking our mail server. Our team is currently working on putting a shunt in place and getting delisted which should take 24-48 hours.

-ZoneEdit Support

 

[simes]

Thanks - will you let me know here when you think it should be working?

One of the difficulties with this is that I can't tell when it is and isn't working 100% of the time...

Regards

--
Simon