Email bounce back error 554 5.7.1

[Parabolic33]

Hello,

I am experiencing an issue with certain users when trying to receive emails from a particular domain. As a quick background the two users experiencing the problem have always been able to receive messages from the senders. The users on my side are using Outlook 2003, Windows XP SP2, and SAVEE 10.

As of last week, when the two senders email my two users, the email does not come through to their outlook inbox, and the sender recieves the below message only half of the time.

554 5.7.1 The message from (<xxx@nakop.com>) with the subject of (DEV: Question for Fluckuation and Max--Please Advise) matches a profile the Internet community may consider spam. Please revise your message before resending.

To try and narrow down the issue I had the senders send test messages to my email address at our work domain and a hotmail account. 8 out of 10 messages made it into my outlook, while all 10 made it into the hotmail account. The senders did not receive any bounce back notifications when sending to me.

I've also contacted my mail provider as we still use POP3 and they have run tests and found nothing on their end. The only thing I can still think of is that they do not know what is going on and they have a content filter up.

I've checked posts on the internet and ran the senders ip address through the SORBS and SpamCops databases and nothing is found. Any help would be greatly appreciated as I don't know where else to check.

Thanks,
Mike

 

[smah]

matches a profile the Internet community may consider spam. Please revise your message before resending

This sounds to me like the message is being and examined (spam profiling ) for content and construction against some 'likely spam' index. Please Advise in the subject may be a flag, for example. If it's HTML, try reformatting as plain text. Remove any included images like company logo's.