Windows NT and Windows 2000 default includes support for three LPT ports. You
can have up to 9. To add ports:
Hive: HKEY_LOCAL_MACHINE
Key: Software\Microsoft\Windows
NT\CurrentVersion\Ports
Name: LPT4 valid lpt1 – lpt9
Type: REG_SZ
Value: leave
string blank
Settings for the currently active serial ports are listed in the values
in the following key. Settings made in Control Panel to change the serial ports
are listed here. HKEY_LOCAL_MACHINE\HARDWARE\RESOURCEMAP\LOADED PARALLEL DRIVER
RESOURCES\Serial
