Microsoft Exchange Proxy Settings Page
Fill out the following.
1 – https://email.hostaccount.com
2 – Check the box next to: Only Connect to proxy server that have this principal name in their certificate:
3 – Enter msstd:email.hostaccount.com
4 – Check the box on fast networks
5 – Check the box on slow networks
6 – Change NTLM Authentication to Basic Authentication
7 – Click OK