To determine why only IP addresses but not host names work for connections to remote computers
1. Make sure that the appropriate HOSTS file and DNS setup have been configured for the computer by checking the host name resolution configuration using the Network icon in Control Panel and then choosing the DNS tab in the Microsoft TCP/IP Properties dialog box.
2. If you are using a HOSTS file, make sure that the name of the remote computer is spelled the same and capitalized the same in the file and by the application using it.
3. If you are using DNS, be sure that the IP addresses of the DNS servers are correct and in the proper order. Use ping with the remote computer by typing both the host name and IP address to determine whether the host name is being resolved properly.