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Unable to connect to COM Port greater than COM20
#1
Whenever I remove and re-pair my bluetooth GPS receiver, Windows 10 assigns a new COM port pair and increments the port number.  I am now at COM24 for the output port and BktTimeSync seems unable to list available COM ports over COM20.  Can you possibly add support for higher COM port numbers?

Thanks & 73,
Barry N1EU
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#2
I found a work-around solution to this after much searching. Windows marks COM ports as used once they are allocated. Bluetooth Devices keeps incrementing the COM ports when you re-pair the GPS because it thinks the old COM ports are in use. You need to go into regedit and change the value of HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter\ComDB - you can find details at http://www.ftdichip.com/Support/Document...gistry.pdf - every COM port has a bit in the ComDB value that is set to 0 if it's available or 1 if it is not. So you need to change the 1's to 0's and then you will once again be able to assign the lower COM ports.
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#3
Hi Barry,

you can also change the port number from the device window. Look here : https://plugable.com/2011/07/04/how-to-c...windows-7/
73 de Mauro, IZ2BKT
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#4
No, that method will not work Mauro if the COM port number has been used before and the bit was never reset in the ComDB registry key. I tried that method first and it told me the COM port was already in use so I had to go into the registry and clear it.
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