How to rename COM port numbers in Windows


I have a set of multiport serial adapters each of which has 8 serial ports on my system. When i install my driver on this controller multiple times, each time the COM port number association with the serial port device changes.

For e.g. During first install, for a serial port device on the adapter on PCI bus 10 and device 2, the COM port number is COM12. On teh second install it changes to COM11. COM12 gets assigned to some other device on this adapter. I want to make sure that everytime i install my driver, the serial port device on PCI bus 10 and device 2, gets the same Port name COM12.

Is there anyway i can achieve this?

What happens if you uninstall the driver first, and then reinstall it?

Sorry i couldn’t understand the query. for re installing the driver anyway
i have to uninstall it right?

Or did you mean re installing as opposed to upgrading the existing drivers?

If yes, the even in case of re installing i still see the same issue. The
COM port number gets allocated to a different serial port.


On Thu, Oct 30, 2014 at 9:16 PM, wrote:

> What happens if you uninstall the driver first, and then reinstall it?
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Post your INF file.

Do you have PortSubClass registry value?

I got a confirmation from one for MSFT members Mr. Doron that the order of enumeration of COM ports and the order of driver installation over these COM ports is not guaranteed. hence i have to write an application that re arranges the COM port number assignments to the respective ports.