Exchange Note to Self - Contacts

I came across a new thing today in our OU and I wanted to document both what I found and how I changed our settings. I came across a few contacts, where all other listings are Users or Groups.

We had three "contacts" setup in our list of users who have email accounts outside of our mail system. As far as I could tell, they had no account or email with us, but they were members of two internal distribution groups. The only options I have with these contacts is to add to a group, move, delete email addresses, open home page or send mail.

My boss asked me to delete these accounts today and forward the mail to him. I couldn't forward their mail, as it existed off our server, and I couldn't disable the contacts as far as I could tell either, not did I really want to do this. Instead, I simply removed the two group memeberships from these accounts. Which actually achieved his goal, they will no longer get mail from us.