I am the exchange administrator for my organization.
We have 3 exchange clusters (exchange 2000 SP4), a front end server, and use an SMTP connector to send outbound mail. We use a third-party vendor as a smart host for all our outbound email.
My problem is this:
I am getting complaints that specific emails are routinely not getting sent, and users are getting delay notifications, and then NDR's.
It appears to be limited to emails with .tif attachments. The complaint is coming from my finance department, so this is high profile and very urgent.
We are in communication with the third party vendor, but so far they are telling us the issue is on our end. Now they have told us that before about issues with inbound email that they also handle for us, and we have proven them wrong at least three different times now, so I am not ruling out that the issue could still be with them.
Has anyone had an issue like this and found a solution? I would greatly appreciate some suggestions, thanks!