I have a question regarding Exim (as a relay,) and the handling of attachments. First though, some background:
Production environment ---------------------- 1. Windows 2000 application server using VB code to send emails with pdf attachments 2. Solaris 9 internal relay running Exim 4.51 3. Windows 2000 upstream relay running an ancient flavour of a commercial smtp filtering package Currently, a user of the win2k app server can generate an email with a pdf attachment. I believe the app code uses the much maligned cdonts to produce some sort of mimeole encoding (I can't really elaborate since windows voodoo is a little beyond me.) The email rockets through the internal Exim relay. Exim sees that this is a non-local delivery and fires it to the upstream relay. This, in turn, delivers the email to the final destination (somewhere out on the 'net.) The recipient receives the email and does clever things with the pdf. All is well - big smiles all round. Testing environment ---------------------- 1. Windows 2000 application server using VB code to send emails with pdf attachments (no change) 2. Solaris 9 internal relay running Exim 4.51 (no change) 3. A new upstream relay appliance (destined to replace the ancient win2k relay) The problem ---------------------- Now...in the testing environment, the same message generation process fires the email through another internal Exim relay. Initially, this relay was running 4.51, but I have since compiled and tested against 4.69 too. Unfortunately, the new relay appliance chokes on the email with a complaint about uuencoded attachments. However, if the app server sends the email directly via the new relay appliance (i.e. removing the Exim relay from the equation,) the email arrives at the final destination normally. As far as I know, attachments are encoded and decoded by the client. The mta simply handles the delivery as-is. Obviously, if the mta is virus/malware scanning, then it has to decode the attachment...but generally, the mta is passive as far as the attachment is concerned. Is there some Exim attachment handling that I'm missing? For the life of me, I can't explain this behaviour (from an Exim perspective.) The vendor of the new appliance has not been particularly helpful so far. The finger has been pointed at Exim as the cause of the problem and their support staff clearly stated that uuencoded attachments are not supported. I have requested an engineering escalation because I can't understand firstly, why uuencoding is not supported and secondly, I can't see why this problem would occur. So far, my questions have fallen on deaf ears, so I thought it wise to turn to the list in the meantime. Any help/suggestions gratefully received! Thanks Paul -- ## List details at http://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
