> [...] and having spoken to the
> ISP it's a typically response ("no one else is having problems") and
> their logs don’t show anything to them outta the norm (their AV logs
> don’t show any cock-ups).Unless you have access to the plain text logs and spool directories from the A/V system at the ISP you cannot know that to be true. If you can install a more capable mail client on each end (such as Thunderbird perhaps) then you will have easy access to the plain text source of each mail (via ctrl + u in TB client) and can inspect the source encoded mail and destination copy more closely. Are the mime headers correct in terms of offset. are things being truncated? "Helpful" line ending conversions mussing things up? 7bit<->8bit conversion? If they refuse to work with you, then you are likely up the proverbial creek since it is out of your control. You will have to switch ISPs or bring all portions of the mail system in-house (of which the latter is normally a better solution for all but the smallest shops anyway IMO). There's a *very* slight chance of a network problem being at fault. Cisco devices have a feature that does deep inspection of certain protocols at the application level. Unfortunately, "fixup protocol smtp" is buggy and is known to cause mail deliverability problems though NOT usually ones like you describe. In any case "no fixup protocol smtp" should be entered into the config of any Cisco device between sender and receiver. As other posters have noted, the various mail transport protocols have long had built-in checks and balances to ensure proper delivery. You can't do rar...pity. Can you have people password protect their zip files/office docs? ~JasonG -- ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~
