Question : Outlook 2007 problems connecting to Exchange 2007 Server

Win 2003 Server DC and Exchange 2007 servers were rebooted last night after updates.
Exchange 2007 update rollup 10 was installed. Most users this morning have had to supply a username and password to the dialogue box to login to the Exchange server again via Outlook 2007 using domian\username. Two users out of 100 cannot connect at all using Outlook 2007. Webmail for the users is working fine.

I have tried changing passwords, remove outlook profile (but cannot connect to server to reinstate) taking off domain and then adding them again. Tried another PC, same issue.
"The connection to Microsoft Exchange is unavailable"

On the same AD domain, can ping ping both DC and Mail server

More worringly I've just tried to add a new user and we are getting the same message
"The connection to Microsoft Exchange is unavailable"

Answer : Outlook 2007 problems connecting to Exchange 2007 Server

Hi,

Create one test user on  exchange server. Try configuring test exchange account in outlook 2007 and at the same time check the connection being establish or timewait on the client side along with port numbers through command line mentioned below.

netstat -n | find "enter you exchange server IP" in case if the connection is being establish on the different port which is not allowed under your firewall then you also have to allow that port on the server firewall and check if it works.

Meanwhile I would also suggest you to configure test exchange user account with using exchange server IP address and check if it is working for you.