We have a client who keeps getting bounces which say the same thing:
This message has been rejected due to content judged to be spam by the internet community IB212 <http://x.co/crbounce>
We have checked with mail hosting company, local ISPs, DNS company and no one seems to be able to give a solution. The emails going out are nothing out of the ordinary and are not spam. Problem started about 3 weeks ago and is only maybe 5% or less of emails, but client is also reporting emails not making it to clients and no bounce, so makes it kind of a problem.
552 This message has been rejected due to content judged to be spam by the Internet community. IB212
The email message contains a link, attachment, or pattern caught by our filters as spam.
Please include an option to opt out in your email messages. Then check your sending lists to ensure you are only sending to recipients who have selected to opt in to receiving your mail. If you feel this message has been flagged as spam erroneously, please be sure to obtain a copy of the original message attempting to be sent, and then contact support.
I suspect this is because the recipients’ ISPs or email providesr hasve an over-aggressive spam filter, and - rightly or wrongly - they have blacklisted your IP address - or even an entire block of IP addresses used by your own ISP.
I’ve seen similar problems several times recently (but not with the same message as yourself). A group of UK universities were using a spam filtering service that blocked all emails coming from my own ISP. It seems that, at one time, a lot of spams were detected, from another customer of the same ISP. So the filtering service simply blocked the entire range of IP addresses. I contacted my recipients at the universities in question, explained the situation, and asked them to complain to their IT departments. I don’t know if that had any effect, but the problem does seem to have gone away now.
More recently, I had a similar issue with Hotmail addresses. For several days, Hotmail was blocking all emails from my ISP. I’m not certain, but it looks like that’s gone away as well.
You can test this yourself by sending two identical emails to a sample of of your recipients. In each case, send one through your normal system, and another from a different IP address or email service. Ask the recipients to let you know which ones they receive, and compare the results.
Thanks for the comments, we have tried using the email account on different local ISPs and also through webmail directly, and there is no consistent partner and even further messages from the same receiver sometimes get through and other times they do not.
One thing I have been noticing is alot of html emails send by the client, with embedded links, also jpg attachments, could this be a cause?
At this point I am thinking we have 4 or 5 small issues which are combined creating a larger issue.