Page 1 of 1

KCOM SMTP Email issues.

Posted: Tue Aug 29, 2023 2:48 pm
by Rob Swan
I have been told by KCOM users of two issues with the KCOM SMTP server (smtp.karoo.co.uk).

It is not clear if these are faults or by design, although what is clear is that previously these issues did not exist.

What is very strange is according to what I have been told it does not affect all KCOM users (not sure if I believe that).

For those who don’t know, KCOM is a UK ISP, who has a reputation of being one of the best. Which make this even more surprising.

The KCOM smtp sever does not require authentication it just checks that you are connected to the internet via KCOM.

Finally, it is also not clear how long this has been going on.

The First Issue.
When sending emails via smtp.karoo.co.uk to a webserver that is connected using KCOM they are not getting through, instead they are getting bounced with the following error.

Final-Recipient: rfc822;me@mydomain.com
Action: delayed
Status: 4.0.0 (temporary failure)
Diagnostic-Code: smtp; 4.4.0 - Other network problem '[Errno 61] Connection refused' (delivery attempts: 0)

Even though the error says “temporary failure” they never get through. The error [Errno 61] means there is no server available at the IP address for the domain.

If you send an email to the same address using any other email account they work perfectly, so the error is complete nonsense. So, for whatever reason the KCOM SMTP server is unable to root emails to a home users IP address on the KCOM network. I have no idea if this effects KCOM business accounts.

It does not appear to make any difference what type of web server you are running either, however I am unable to verify this 100%.

The Second issue.
Servers on the KCOM network are unable to use SMTP relay via the KCOM SMTP server, instead they are just reporting a timed-out error when trying to connect to smtp.karoo.co.uk, as these servers are connected to the internet via KCOM there is no reason why they should not be able to connect.

A lot of KCOM IP addresses are listed on online spam databases so users with home mail servers need SMTP relay to be working in order to send out emails.

What can be done?
The sending issue is up to KCOM to sort out (if it’s a fault and not by design), however SMTP relay can be done via other free SMTP servers instead of the KCOM one.

As the amount of people that are using the free KCOM’s email address (provided only to its customers) this is not a major problem, but I felt I should write this post just in case any users are blaming their web server for this issue.

I have not had any reports on any other ISP with SMTP issues, however this does not mean it is not happening. So please let me know if you have the same issue with another ISP.

I am aware of some UK mobile operators closing down smtp servers, maybe fixed line ISP’s will do the same thing at some point.