Windows XP, CAT and problems with COM10, COM11 etc.

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Windows XP, CAT and problems with COM10, COM11 etc.
Image icon computer.jpg60.02 KB
Image icon management.jpg86.21 KB
Image icon properties.jpg28.2 KB
Image icon advanced.jpg23.79 KB
Image icon setport.jpg69 KB

Hi. I discovered this week that on my copy of Windows XP (SP3), Hamlib (used by WSPR for CAT rig control) will only work with COM ports COM1 - COM9. Ones with double digit numbers (COM10, COM11 etc.) just get back the dreaded:

serial_open: Unable to open COM10 - Invalid argument
rig_open: error = IO error

This happens with both my newly-installed 2 Port Serial IO PCI card and my Serial to USB Adapter.

Is anyone is successfully using COM10 or higher on Windows Vista or Windows 7??

For Windows XP, the workaround is to change the COM port name - see instructions below. By the way, be aware that if you move Serial to USB Adapters around different USB ports, Windows XP marks COM ports as "in use" when it's really just reserving them for if the same USB port is re-used - providing they really aren't in use, you can allocate the "in use" ones to a serial port. (Best to avoid COM1 and COM2 though.)

I understand that there is a known issue in Windows with COM ports that affects Hamlib but other software has a workaround in.

Changing COM port name (XP or Vista)

See picture computer.jpg:

[1] Click the "Start" button
[2] Right-click on "Computer"
[3] Choose "Manage"

See picture management.jpg. In the "Computer Management" window:

[4] On the left, click on "Device Manager"
[5] On the right, click the "+" sign next to "Ports (COM & LPT)"
[6] Under "Ports (COM & LPT)", right-click on your USB to Serial Port
[7] Choose "Properties"

See picture properties.jpg. In the "... Properties" window:

[8] Click the "Advanced..." button

See picture advanced.jpg. In the "Advanced Settings for COM.." window:

[9] Click the dropdown arrow for "COM Port Number:"

See picture setport.jpg.

[10] Choose a COM that is between COM1 and COM9. (This can be one that is marked "in use" if you're sure it isn't really in use, but it's best to avoid COM1 and COM2.)

[11] Click "OK" to close the "Advanced Settings" window

[12] Click "OK" to close the "... Properties" window

[13] Set up WSPR to choose the new COM port and see if it is now working.