PROBLEM:

While having Outlook configured to use RPC over HTTP, Outlook connection the Exchange server is extremely slow. Once Outlook is opened after the initial configuration, users do not get the authentication prompt from anywhere between 1min – 3 min.

 

CAUSE/RESOLUTION:

To resolve the issue we configured the user profile in outlook to use HTTP first and then fallback to TCP/IP on fast networks. This setting was found on the More Settings options\Connection Tab\Exchange Proxy Settings. We checked the box marked “On fast networks, connect using HTTP first, then connect using TCP/IP”.

 

After configuring this setting we updated the client machines with the latest SSL Certificate that we created after running the Internet Connection Wizard (ICW). Now when users open Outlook they are prompted almost instantaneously for credentials.

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