4.4.0 other network problem

[#1]

We have Plusnet business fibre broadband and recieve Email from lots of people.

However, one company SSE.COM  can not Email us, (we can send Email to them).

I check it never reaches our server on site.

They claim to be able to Email send to everyone else.

When they Email send, they receive the message back :   4.4.0 other network  [Errno 0] error

Moderators Note

Image amended to redact personal information.

[#2]

Hi @MouseRunner,

I'm sorry to hear that this company is running into this issue. Are you able to add them to your whitelist via the spam settings to see if this makes any difference? Would it also be possible for you to ask them to do the same with your email address?

[#3]

I think you misunderstand.  We are not using PlusNet Email.

We have our own Email server (MS Exchanage) connected via PlusNet Fibre Broadband.

Unfortunately Email from this one company is not reacting our server....

Due to an internet problem.

Could it be that they are on IP v6 and we are on IP v4 - causing some delay ?

[#4]

I recognise the reply -  Is your email server using greylisting ?

[#5]

Moderators Note

This topic has been moved from Fibre to Business

[#6]

Hi @MouseRunner

A quick look into the error message shows a few different reasons.

It could be the senders server timing out due to either the senders firewall releasing emails in trickles or poor bandwidth. If they're sending large quantities of emails it could be timing out before it gets sent to you.

It could potentially be the IPv6  vs IPv4. The sender would need to check their  DNS record to see if you have implemented a SPF record for ipv4 and/or for IPv6.

And also it could be a DNS lookup error on the senders side.

From what I can see, It looks like the issue is with the sender and nothing on your side. It's somewhat reinforced by the fact that they can receive emails from you too.

[#7]

From research on internet, I agree it "could be the senders server timing out"

Although they claim: we are the only one reporting the problem.