RPC over HTTP - Domain Member Laptop on an Ethernet DSL with NAT

[Brad M]

Hi,

Outlook is installed on a laptop which is a domain member and ethernet
connected - outlook connects TCP/IP OK.

If the same laptop is using a USB CDMA broadband internet connection,
Outlook connects HTTPS OK.

How do I make the laptop connect HTTPS using an ethernet connected DSL
modem? The laptop always tries to connect TCP/IP when ethernet is the network
connection.

thanks in advance
Brad

 

[neo [mvp outlook]]

Where you configure the RPC/HTTPS settings in Outlook, you need to check
both boxes to try HTTP first on fast and slow network connections.

 

[Brad M]

Hi neo,

thanks for the reply, I had both of those options checked already.

regards
Brad

 

[neo [mvp outlook]]

If you start Outlook with the /rpcdiag switch, does it show Outlook cycling
thru both connection types?

 

[Brad M]

Hi neo,

Confirming Config

Exchange Profile/General tab
When Starting Automatically detect connection state, timeout 30seconds

Exchange Profile/Advanced
Use Cached Mode

Exchange Profile/Security
Kerberos/NTLM Password Authentication

Exchange Profile/Connection
Connect using my LAN
Connect to my Exchange mailbox using HTTP

Exchange Proxy Settings
URL mail.domain (same name internal and external)
On fast networks connect using HTTP first, then...
On slow networks connect using HTTP first, then...

Basic Authentication

TESTING RESULTS - the laptop was disconnected from each network type,
connected to the new network and restarted between each test

On the domain ethernet
Outlook launched with /rpcdiag,
Outlook prompts for domain credentials (for the exchange server) which were
entered and accepted OK
Connection status shows ---'s for a little while then eventually outlook
connects TCP/IP (what happened to HTTPS?)

On CDMA Broadband USB device
Outlook launched with /rpcdiag
Outlook prompts for domain credentials (for the exchange server) which were
entered and accepted OK
Connection status shows ---'s briefly then outlook connects HTTPS

On DSL Broadband modem (which has NAT/DHCP)
Outlook launched with /rpcdiag
Outlook prompts for domain credentials (for the exchange server) which were
entered and accepted OK
Connection status shows ---'s (there is no interface name present)
Clicking "reconnect" has no effect

thanks again
Brad

 

[neo [mvp outlook]]

The only things I can think of at this point is that "mail.domain" resolves
to something unexpected when on the domain and dsl connection. When you are
on either connection and perform a nslookup -q=A mail.domain, do you get the
IP address you expected to see?

I would also check IIS configuration. For example, does the RPC/HTTP proxy
server only accept connections from specific IP address(es)?