Hi,
I saw a lot of discussions about removal of X400 address type. We have it also implemented from previous versions of Exchange. Now we are only on 2013 and want to migrate to 2016. But before migration I would like to remove all X400 addresses.
We have X400 defined in default "email address policy". I can remove it there and update all mailboxes to reflect changes on address policy.
But my question is - What happened if I remove X400 from default email address policy and outlook will use cached email contact with SMTP/X400 address? I would like to avoid problems which cause NDR emails coming to employees just because their outlook has cached items.
Thanks