External Mail Server refusing mail

[MAY1974]

Every time I try to send mail to a particular email address.

I get this message:-

This message uses a character set that is not supported by the Internet Service. To view the original message content, open the attached message. If the text doesn't display correctly, save the attachment to disk, and then open it using a viewer that can display the original character set.

I've tryed sending the message as a unicode attachment.
Formatting the messaga as plain text and rich text format.

Completey stumped.

Has anybody else run into this problem??

 

[kgoods]

I have not had that problem myself (sending), but I have been receiving a bunch of emails with that verbage. It is invariably spam so I haven't paid much attention. I'll make a mental note to look at the header of the next one I receive and see if that doesn't shed some light on the matter. I assumed that they were from a foriegn country but now that I think about it the attachments displayed correctly.

Now you have my interest up. I'll take a look and let you know what I find out. May be a couple days before I get another one.

Regards,
Ken

 

[Grover99]

I'm having a similar issue using Exchange 5.5 and various flavors of Outlook. One of the senders whose messages come through like this is "CNN Breaking News". They used to come through fine, so I'm not sure if this was caused by a change on my Exchange server, my mail preprocessor, or in the way CNN formats messages. I also use a Linux box with SendMail 8.12.10, MailScanner 4.20-3, F-Prot 3.12a, and SpamAssassin 2.55 to preprocess mail before it reaches my Exchange servers--all of this had been in place for some time before we started seeing the problem.

Any common thread with you, May1974?

 

[Grover99]

I have some additional information from the header of a problem message:

X-MailScanner: Found to be clean
X-MailScanner-SpamCheck: not spam, SpamAssassin (score=0.8, required 4.8,
APPROVED_BY, MSG_ID_ADDED_BY_MTA_3)
MIME-Version: 1.0
Content-Type: text/plain; charset=unknown-8bit
Content-Transfer-Encoding: quoted-printable
MIME-Autoconverted: from 8bit to quoted-printable by mail-queue.*.com id i3LCDt5f000935 (mail-queue is our Linux mail preprocessor)

 

[kgoods]

I think you hit the nail on the head Grover99.

I see several different charset values for the emails that exhibit this behavior. But none of them are “standard”. It could be a way for spammers to fool the spam-catching software although I certainly wouldn’t think that would be the case with CNN. BTW, one of my users emailed me yesterday and asked if I knew how to unsubscribe from that list (CNN Breaking News) because she was getting the same message.

I too have a Linux box in front of Exchange 5.5 and Outlook 2000. This box runs sendmail, MailScanner, Spamassassin, and Clamav. But I just installed this box at the beginning of last week and I had been getting these messages for the last month or so. Same thing here though. No updates and or changes to any of my MS boxes just prior to these messages showing up.

MAY1974:
Since you’re having the problem with sent messages I would check Outlook’s language settings on both the sending box and the receiving box. I just about bet they are not set the same. It’s under Tools->Options->Mail Format(Tab)->International Options(button).

I’d be interested in hearing if this helps or at least explains it.

Take care,
Ken

 

[kgoods]

Grover99

BTW... I noticed you have Spamassassin's threshold at 4.8.

How is this working for you? And how do you insure you're not loosing valid emails? Eventually I want to simply drop spam at the server but even with a threshold of 6 we've had about 3-5 false positives out of 5-8K emails a day. I know this is a great percentage but the big boss had one of the false positives so I need to be careful.

Thanks,
Ken

 

[Grover99]

Ken--

We sent a couple thousand messages to train the Bayesian filters initially, and since then have followed up with a few hundred more a few times a year. I'd say we still have significantly more false negatives than false positives.

Unfortunately, we put the burden for detecting false positives on the end user--we only tag messages with {Spam?} so that users can sort or filter messages as they see fit. We suggest that users set up Outlook filters to move these messages into a "spam" or "junk mail" folder, then go through them occasionally to check for false positives (which we then add to the filtering software to prevent.) We don't delete any mail, but we do refuse mail from open relays (via SORBS). That lead to a GREAT decrease in traffic over our T1s, as the connection is dropped as soon as an open relay server says EHLO (a Cockney greeting, eh?)--we never even move the message over the pipe or scan it for content/viruses. It's been very successful for us.

MAY1974--

Back to the original question at hand--I have an idea that I haven't yet been able to test re: the character set issue. I'm guessing that the version of SpamAssassin or MailScanner that we're using might not properly detect some of the settings for some new mail products. For instance, I've seen mail sent with OutlookXP or 2003 (and possibly the newer versions Outlook Express) get tagged as SPAM because MailScanner thinks that the "client" tag information is spoofed--it's too old to recognize the newer clients' tags. Anyone know if XP is using some sort of new funky charsets?

 

[kgoods]

Grover99
Sounds like we're set up nearly identical. Thanks for the info. I haven't trained the Bayes yet and the problem I'm seeing is that since auto-learn is on, when a spam does make it through it's learned as not-spam and I'm not sure this is such a good thing. I'll have to hit the manuals again and see how I can un-train these once I get them. I saw that it was possible.

The orginal problem is weird. I was going to change my International Language setting in Outlook just to test it but I'm thinking that the conversion is taking place on the Exchange server so this may not have any effect.

Thanks again,
Ken

 

[MAY1974]

Thanks for all this guys.

I'm sending mail to my ISP ???

This is bizarre...

Changed Outlook’s language settings on both the sending box and the receiving box, not sure if I change it to the right thing though. Also tryed sending from my ntl account and got a delivery failure notice.

I'm trying to email energis.com

 

[Grover99]

May--

The problem with CNN seems to have spontaneously cleared up--maybe someone there is reading this thread? ;-)

Anyway, I can take a look at your headers if you like to see if something along the line is doing the same thing to your mail as was happening to CNN's. Send mail to scheu001(at)hotmail.com and I'll take a look!