Hi to anyone,Hopefully someone can help on this.Sometimes, on client machines, when they try to connect to Outlook, it will fail. I found that the IP Address of the Exchange server had become Public IP instead of the private IP. I have to renew the IP address in order to solve the problem but it keeps happening to all other machines. Anyone had encountered this problem before and if so, how to solve?Any help on the issue is greatly appreciated.Many thanks!TanTan

Hi to anyone,Hopefully someone can help on this.Sometimes, on client machines, when they try to connect to Outlook, it will fail. I found that the IP Address of the Exchange server had become Public IP instead of the private IP. I have to renew the IP address in order to solve the problem but it keeps happening to all other machines. Anyone had encountered this problem before and if so, how to solve?Any help on the issue is greatly appreciated.Many thanks!Tan Tan Hi There,Try to reinstall drivers of Network Adapter or If its DHCP then try to give static Ip address.Sunny Kewalramani

Hey Tan, A late response, but hope it helps. Is it possible that you've configured a public IP Address on a NIC on your Exchange Server and that NIC is configured to register the IP Address in DNS? I'm just trying to figure out why the public IP Address of the Exchange Server replaces the private IP Address. Can I infer from your post that the clients are resolving to the public IP Address of the Exchange Server when they try to connect to it?Ook

If your user receives an outside DNS server from DHCP, or by manually entering, then they may start getting the outside address for your server. Run ipconfig /all in a command prompt on the user's PC and check what they have for a DNS server listed. We have had some our subnets lose their DHCP scope and revert to the server's DHCP scope, so when the users on that subnet renewed, they could no longer get to the mail server. We also ran into this issue when a new assitant admin created a new scope and put in both the inside and outside DNS server. One more example was when an over clever user put in outside DNS server in manually. (We have had viruses do this, too, but I would think you'd have seen other weird behavior on those PCs.)