I have Exchange 2010. 2 mailboxes and DAG. 2 HUB/CAS servers with NLB. MAPI Clients does not connect as TCP/IP. Only Connect as HTTPS. Why ? Because the internal connect failed and Outlook switch to Outlook Anywhere automatically. You may block Outlook Anywhere external URL in local host file, and restart Outlook to see what happen. Generally you might be prompted for authentication or error message that server not found. If this is the case, create a new Windows profile or change to anothe computer and try again. If the issue continues, you might need to collect network monitor log for further analysis. Hope it is helpful. Fiona Liao TechNet Community Support

Where is this client in relation to the server? Did you setup a casarray? Is your NLB the windows NLB or some other software/hardware? Are you getting your info from the Outlook 'Test Connectivity' app? I typically only see http connections if the PC is on a remote network, outside of the main network, or there are some desktop issues. The default is to use TCPIP (MAPI) on fast networks and HTTPS on slow networks. Could you check your client and make sure this was not changed? You could also disable both to try and force it to use TCPIP.

I have Exchange 2010. 2 mailboxes and DAG. 2 HUB/CAS servers with NLB. MAPI Clients does not connect as TCP/IP. Only Connect as HTTPS. Why ? Because the internal connect failed and Outlook switch to Outlook Anywhere automatically. You may block Outlook Anywhere external URL in local host file, and restart Outlook to see what happen. Generally you might be prompted for authentication or error message that server not found. If this is the case, create a new Windows profile or change to anothe computer and try again. If the issue continues, you might need to collect network monitor log for further analysis. Hope it is helpful. Fiona Liao TechNet Community Support

I have Exchange 2010. 2 mailboxes and DAG. 2 HUB/CAS servers with NLB. MAPI Clients does not connect as TCP/IP. Only Connect as HTTPS. Why ?