Async Client cannot connect to Async Server.

We've successfully configured a PROD environment.

Now we're creating a TEST env.  We duplicated the AX, then installed a Async Server on the AOS server, installed store db, Async client on a store server in another domain. 

I can access the WCF https://server:8303/AsyncServerLab/DownloadService.svc  from the store server.

But the test connection failed fron the Async client configuration Tool.

from the event viewer, i see errors below:

Unable to communicate with server for download. Please check username/password, server and database connections. Error Details: System.ServiceModel.Security.MessageSecurityException: An unsecured or incorrectly secured fault was received from the other party. See the inner FaultException for the fault code and detail. ---> System.ServiceModel.FaultException: An error occurred when verifying security for the message.

I've make sure useing the same username/password set in AX's retail setup channel database form. 

Sync metadata succefully.

And we use the same certificate used in PROD evnironment which is obtained from a provider.  (Also tried using self-generated).

Any ideas?

thanks

Feng