wconsd

Look at http://msdn2.microsoft.com/en-us/library/ms535797.aspx

also, this example code: http://www.lookrs232.com/com_port_programming/api_enumports.htm

I have done some research and this appears to be more difficult than it should be.

• PORT_INFO_2 doesn't provide much information (http://msdn2.microsoft.com/en-us/library/ms535509(VS.85).aspx) nrports=12 Port Monitor Desc Type Reserved Microsoft Document Imaging Writer Port: Local Monitor Local Port 1 0 COM1: Local Monitor Local Port 1 0 COM2: Local Monitor Local Port 1 0 COM3: Local Monitor Local Port 1 0 COM4: Local Monitor Local Port 1 0 FILE: Local Monitor Local Port 1 0 LPT1: Local Monitor Local Port 1 0 LPT2: Local Monitor Local Port 1 0 LPT3: Local Monitor Local Port 1 0 COM5: Local Monitor Local Port 1 0 COM6: Local Monitor Local Port 1 0 IcePortER: Ice Monitor E Black Ice Port 1 0
• SetupDiEnumDeviceInterfaces (http://forum.sysinternals.com/forum_posts.asp?TID=4544 and http://msdn2.microsoft.com/en-us/library/ms793116.aspx) doesnt find enough interfaces: DevicePath=\?\acpi#pnp0501!#1#{4d36e978-e325-11ce-bfc1-08002be10318} DevicePath=\?\acpi#pnp0501!#2#{4d36e978-e325-11ce-bfc1-08002be10318}
• There is an entire library for doing this (http://www.naughter.com/enumser.html) that checks seven different methods for com ports, but its licence may be incompatible with GPL