HiRPC over HTTPS has been working for me for couple of weeks, and now it doesn't work. I tried to modify registry, hosts file to disable IPv6 but nothing was changed. When I try to use rpcping to port 6001 I have error Exception 1722 (0x000006BA), rpcping to port 6002 and 6004 works fine.I've two MB one CA and on HT, mb's are installed on w2k3 and HT and CA are installed on w2k8, I've installed rollup 9. Thanks,

Have a look into this. http://groups.google.com/group/microsoft.public.exchange.clients/browse_thread/thread/2540acb126b77ed5Also check for the registry keys in the technet http://technet.microsoft.com/en-us/library/bb124159(EXCHG.65).aspx mbx1:6001-6002;mbx1:6004;mbx1.contoso.com:6001-6002;mbx1.contoso.com:6004 Raj

I think your exchange store service meet some error, you can check your application log to find if there have anything related with this. As you mentioned, Exception 1722 (0x000006BA) means RPC server is unavailable, you can refer to this information: Exception 1722 (0x000006BA) RPC Server is unavailable The RPC service cannot be contacted. You may receive this response because there are problems with the RPC Proxy server (if this is the case, you can use the E argument to verify that the RPC Proxy server is available), because the service stopped on Exchange 2003 backend server (for example store), because the Exchange 2003 backend server is down, because the ValidPorts registry key does not permit access to this server, because the ValidPorts registry key does not permit this port, because you tried to to access the EMP when it was not published (neither the e switch or port 593 were available), or because you tried to access UUID when EMP was not published (for example, you used the a switch without port 593 being available.). At the end, you can refer to this link to fix your issue: http://technet.microsoft.com/en-us/library/cc671176.aspxa245ac8356cd89088a3a0e0536223c20 56cd89088a3a0e05 c093d70f088499c3a837cae00c042f14

Try running below tool from one of client and see what is going on https://www.testexchangeconnectivity.com/Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|

Hi,I must put this registry key to MB's server or only CA. I've multi tier architecture, and on CA I've got this reg key but I haven't one on MB's. Thanks,

Hi,Any update on this issue?ThanksAllen

Hi,I think on MB's server there are missed registry entries. I used rpcdump and there is no entry about 6001 port. In bindig order reg key ther are only two entries ncalrpc, ncacn_ip_tcp but in this article http://support.microsoft.com/kb/325930there is information about such entries ncalrpc,ncacn_ip_tcp,ncacn_spx,ncacn_np,netbios,ncacn_vns_spp. Another thing is when I run portquery -n hostname -e 135 I can't see any entries with port 6001Thanks

Hi,Did you try the steps on the above link (KB325930)?ThanksAllen

Hi,The problem has been resolved. One guy from this company has installed software NetSupport DNA, this software use 6001 port for communication.Thanks for your help

Hi,Glad to hear that is resolved by self.ThanksAllen