For Windows NT - based clients, when dbopen is called with the name of a SQL Server to connect to, DB-Library uses the configuration information in the following subtree of the Windows NT Registry:
HKEY_LOCAL_MACHINE\
SOFTWARE\
Microsoft\
MSSQLServer\
Client\
ConnectTo
The entries of the Registry are values in the following format:
value:REG_SZ:Net-Library_Name[,network_specific_ parameters]