I have a rather odd problem with my exchange server (exchange 6.x on SBS 2003), which has emerged only recently when i changed the 'primary email address' of some of my users from our original domain to a new one which we set up. Basically it seems like some of the users cannot send from their email addresses - they get a NDR with the generic no permission message 'You do not have permission to send to this recipient. For assistance, contact your system administrator.' The strange thing is that it only seems to be a few of the users - and also that it is not always the same domain that works/doesnt work (which seemed extra odd - as some of them are now not able to send emails from addresses they previously were able to. I have double checked that they have the 'send as' permissions on the account, and have tried everything i can think of, although exchange isnt really my forte so is there something else i should try? I also have set up most of the possible exchange diagnostics, but i cant seem to find anything in the (now spiraling) event logs that even tells me what the NDR is being created for. (is there some specific diagnostics i should look for - i set them all now and cant see the wood for the trees) I have telnetted into the SMTP server and can send email pretending to be from the users fine so presumably it is something to do with outlook profiles - or at least something that happens before it actually gets queued. I read one forum post where someone had a similiar problem and thought that they could solve it by deleting the user and starting again, but i would like to try and avoid doing this - it seems a bit of a time consuming and rubbish solution.

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