We have a couple of Outlooks that continually populate bad email addresses in the cache/nickname (NK2) file.
It only appears to affect one recipient, but after a few days the address in the cache ends up pointing to a user that doesnt exist.
For example; User1 sends to user2, putting in the address using the 'check name' feature, all is well. Next time user1 tries to send to user2, they use the cached address and the email bounces due to the recipient not existing on the exchange server.
Looking into the details of the bounced mail, we can see the path to the user reference is bad
/O=THEDOMAIN/OU=FIRST ADMINISTRATIVE GROUP/CN=RECIPIENTS/CN=USER262156485
There never was a user262156485, it should obviously point to user2... I have no idea where it picks up this reference.
I've tried deleting the bad reference out of the NK2 through Outlook, and with various tools. I've tried deleting the whole NK2, but after a few emails the bad reference comes back.
So my question is; how can I get rid of the reference so that I can ensure that it doesnt come back?