Problems with e-mail since 1st June - re-written h...

Question

I collect my e-mails via a client using pop3. For 15 months no problem but since 1st June (and after having to change my password) the routing of e-mails into my e-mail client's folders has steadily deteriorated. They all end up in the "Dead Letter" folder Nothing has changed this end and the same thing is happening on my wife's laptop which runs a parallel system. This problen has been seen before on another ISPs e-mail and arises because suddenly the headers are being re-written. I wonder if I have been transferred to the new system. This is a known issue with MS Exchagne based e-mail systems. Now we are finding that some outgoing e-mails are going missing. Some people on a standard distribution list are receving a copy and some are not. Anyone else experiencing any problems?

Answer 1

I have also noticed issues with the email headers.
From looking at incoming email headers, I have spotted that some (but not all) of the BT Spam Guard servers have been adding a blank line to the SMTP header.
For example, this is an excert of a bad header:
<snip>Received-SPF: none (smtpin20.bt.ext.cpcloud.co.uk: domain community.bt.com
 does not designate permitted sender hosts):
X-CTCH-RefID: str=0001.0A090209.5227AE11.00E9,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0
X-CTCH-VOD: Unknown
X-CTCH-Spam: Unknown
Received: from smtp2.lithium.com (46.19.168.11) by smtpin20.bt.ext.cpcloud.co.uk (8.6.100.06)
        id 52260CF90060421F for [email protected];
</snip>
Whereas this is an example of a good SMTP header:
<snip>Received: from IS-14641 (109.169.50.17) by smtpin03.bt.ext.cpcloud.co.uk (8.6.100.06)
        id 52132CC904D91E2C for [email protected]; Tue, 3 Sep 2013 10:41:09 +0100
Received: from [127.0.0.1] (IS-XXXXX [127.0.0.1])
    by IS-14641 (8.13.8/8.13.8) with ESMTP id r839f80c018824
    for [email protected];
</snip>
So because of the blank line, some mail related programs are interpreting the part after the blank as the body of the message, even though the final destination and subject lines are included in the part after the blank.
I would guess that some of the anti-spam servers have been misconfigured as the SMTP standard does not allow for blank lines within the header.
Hopefully this will be fixed as it is playing hell with some programs such as MailWasher Pro that I use to flag emails that do not have my address in the To, CC or BCC fields as spam