Hi We have a consultant who has a company email account on our Exchange box but also needs to access work emails from offsite (which is about 50% of the time) so we set up a Contact pointing to his external email address. Due to his work requirements (don't ask ... please) he accesses his emails from his external account nearly all the time so the forwarding setting on his mailbox did not have the 'Deliver messages to both forwarding address and mailbox' checkbox set. All was fine. Recently we needed his mailbox to receive emails as well so the above checkbox was checked - straight forward (excuse) it seems as this is done on other mailboxes quite happily (I get emails forwarded from a system box the same way). But the next morning I get contacted by him saying he is getting two copies of every email forwarded from the exchange mailbox. I check our external mail website and Yes two copies are arriving from our system and going on to his external account. I create a Contact for my external mail address and send numerous test emails while altenating between checking/unchecking the aforementioned setting and obtained exactly the same result - if the mail was forwarded straight on only then I received one email in my external account, if the mail went to both the exchange mailbox and forwarded on then I received two copies. Any ideas out there? We have a Sophos 'Pure Messenge' AV scanner on the mail server so I want to check if this has been seen before as an Exchange issue before I go turning other services off for further testing.

OK - after more deciding on mail accounts between domains it looks like this was not an Exchange issue and the spotlight fell on our Sophos PureMessage application that hooks into Exchange. I inherited this when I joined this year so do not have indepth knowledge of it and how it works, but I (now) suspect that, when Exchange sends a message to both the mailbox and the contact, PureMessage is seeing two separate messages at the level it is connected into Exchange and thus processes two separate emails itself. Quickly tested by stopping the PureMessage engine and sending a barrage of emails to the test Contact I created, then starting PureMessage and doing the same. Checking my external email account saw that when PureMessage wasn't running I received just the one message per email but when PureMessage was running again I started to receive duplicates. Off to the Sophos site now, apols for clogging the forum but hope I provided a bit of light entertainment for the day.