Emails to plus.com email addresses rejected

[#1]

Emails from my hosted domain to any plusnet hosted email address are being rejected with the below error. I have configured SPF, DKIM and DMARC. My IP is not listed on any blacklist that I can find. Does anyone have any idea what is going on? Is it possible that plusnet has blocked me?

I have sent an email to abuse@plus.net on 1st Feb but haven't received a reply.

I can provide more detailed information about my domain in a PM or direct email if someone from plusnet can advise?

Thanks,

Matt.

--------------

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  email@[removed].plus.com
    all hosts for '[removed].plus.com' have been failing for a long time (and retry time not reached)

--1606314674-eximdsn-1079202992
Content-type: message/delivery-status

Reporting-MTA: dns; medon.uksrv.co.uk

Action: failed
Final-Recipient: rfc822; email@[removed].plus.com
Status: 5.0.0

Moderator's note by Mike (Mav): Personal information removed from a public forum (to an area that staff can see).

[#2]

The email address is still behind the links in your post as a heads up. I’ve asked the mods to edit it out as there’s a 20 min time limit for normal users to edit posts.

If you put your IP and domain in the Spamhaus lookup tool here https://www.spamhaus.org/lookup/ does it show any blocks on your IP and/or domain?

Failing that you may need someone like @Townman to cast an eye over this and have a look.

[#3]

Thanks for the reply. I have checked the spamhaus lookup and neither my IP nor domain is on there.

[#4]

I have just tried again. This is the bounceback received. Is anyone able to help, please?

Thanks.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

user@domain.plus.com
retry timeout exceeded
Reporting-MTA: dns; medon.uksrv.co.uk

Action: failed
Final-Recipient: rfc822;user@domain.plus.com
Status: 5.0.0

[#5]

Do you have any URL links in your email sig ? These can often upset the Cloudmark Spam detection system.

[#6]

Thanks for your reply. No URL links in the email sig. Just standard stuff with name and a disclaimer.

Its not just me having this problem; anyone emailing from my domain is having the same issue sending to any email account hosted with plusnet.

Is it possible that my IP is blocked? My server admins tried a telnet on port 25 and that timed out.

Any other ideas?

[#7]

My server admins tried a telnet on port 25 and that timed out.

That sounds strange! Normally you would get as far as authentication at least and then it would return a 535 see here  for an example https://community.plus.net/t5/Email/Unable-to-send-emails-POP-when-using-Plusnet-broadband/m-p/17731...

Note the example is using port 587 since its simulating submission from am email client. MTA's would normally use port 25 to relay but that shouldn't make a difference

[#8]

Is there a VPN involved here?

[#9]

@Townman Thanks for reply. No VPNs in use. Just plain old webmail.