Am on Os X Yosemite,apple  mail 8.2 . All is well except the delivery of exchange mails. They are hanging in the outbox, severally synchronizations fails messing mail organization, On my machine the mail presentation is right but on forwarding the same message to other users its messed up and many more.

>From the advise in apple forums nothing seems to work. Currently I have incoming mail with the public mail server address and the outgoing with the local server IP. Incoming mails speed slowed and the speed improved on sent mails.

For those who faced this challenge, Advise 

The gate Keeper.