SolidWorks Network clients and PDM clients are normally set up to connect to the server using the system host name. The host names are resolved to IP addresses. The client will not be able to connect if there is a mismatch between the server host and the IP.
Whenever a new program is installed, new folders are created in the registry containing some settings about that program. This is not different for SolidWorks. Deleting or renaming the Solidworks registry folder will erase any trace of the previous settings and the software will generate a new set of registry keys on the next launch.