Mail blocked but ip not on blocklist?

[Black Tiger]

Hello.

I don't post here very often so I hope I'm doing it correctly.

Several users on our hosting server get mail which they send to other users back, even when they send email to users with the same domain name. When I lookup the problem, it says mail is blocked by spamcop (I masked the receiving domains):

This is from the log

2013-12-06 12:47:55 H=fep19.mx.upcmail.net [62.179.121.39] F=<verkoop[at]domain.nl> rejected RCPT <wouter[at]domain.nl>: Email

blocked by SPAMCOP - to unblock see http://www.spamcop.net/fom-serve/cache/76.html

2013-12-06 12:47:55 H=fep19.mx.upcmail.net [62.179.121.39] incomplete transaction (RSET) from <verkoop[at]domain.nl>

2013-12-06 12:47:55 H=fep19.mx.upcmail.net [62.179.121.39] F=<> rejected RCPT <verkoop[at]domain.nl>: Email blocked by SPAMCOP -

to unblock see http://www.spamcop.net/fom-serve/cache/76.html

2013-12-06 12:47:55 H=fep19.mx.upcmail.net [62.179.121.39] incomplete transaction (RSET) from <>

Now I know that the upcmail.net ip is on some lists, but this ip is not present on the bl.spamcop.net.

Neither is the ip belonging to our hosting server, which is not present on any blacklist.

So how is it possible, that the mail gets blocked by spamcop, when neither ip's are on the spamcop blacklist?

There are multiple users which use upcmail.net having this problem but again, upcmail.net's ip's are not on bl.spamcop.net when I do a search.

What can be done to solve this problem please?

[SpamCopAdmin]

62.179.121.39 = fep19.mx.upcmail.net was removed from our list on

Friday, December 06, 2013 05:26:58 -0700 because the spam stopped

for some reason.

It has been going on and off our list for a couple of weeks.

- Don D'Minion - SpamCop Admin -

- Service[at]Admin.SpamCop.net -

.

[turetzsr]

Hello.

I don't post here very often so I hope I'm doing it correctly.

<snip>

...FWIW, it looks correct to me! <g>

So how is it possible, that the mail gets blocked by spamcop, when neither ip's are on the spamcop blacklist?

<snip>

...First, please bear in mind that SpamCop can block nothing because SpamCop's servers don't handle any e-mail.

...Second, please do not assume that the messages you are seeing are constructed by a competent and truthful entity; there are occasions when messages indicate that an IP address is on the SpamCop blacklist when in fact it is clear that some other criterion must be being used as the reason to block because that IP address has never been on the SpamCop blacklist, much less currently on the list, or the IP address was removed from the blacklist some time back and perhaps the party trying to use it has not refreshed with the latest list.