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Windows 10 serial port COM port changes

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I have an ordinary Lenovo PC running Windows 10.  To it, I've installed several multi-port serial ports.  Everything worked UNTIL I rebooted.  Before, COM port numbers had gaps but now it's sequential.  There is nothing wrong with sequential numbers but I'm not liking the fact the numbers changed by rebooting.

I did look around and appears this is a common complaint.  There seems to be no concrete and sure way to fix it.  What a silly oversight by Microsoft!

I'm planning to use these ports to control test equipment.  It would be really confusing if this happens every time.  How do deal with this??

This is the card I use.

Just like previous version of Windows, you should be able to assign specific com ports in:

Device Manager -> Ports -> (select desired port) -> Properties -> Port Settings -> Advanced

P.S., if you need to see any "hidden" comm ports from devices that Windows can't see at the time, have been removed, unplugged or disabled, you can do the following from a command prompt:

set devmgr_show_nonpresent_devices=1
start devmgmt.msc

I had to do this about a week ago on a Windows 2000 machine that I swapped a new motherboard into at the car wash...  The machine has several RS-485 to RS-232 converters connected to it that go to the various PLCs controlling sets of 4 bays, allowing monitoring and control.  Some are on the on-board ports, others are on serial cards, it also has a USB modem connected to it and an old leftover Winmodem...  I didn't want to mess with the software configs, etc. (I didn't set this up decades ago :) ) so I just cleared all the old ones and moved the important things back to where they were previously like com:2,4,5 instead of 11,12 and 17 or whatever crazy high numbers they had been re-detected on after swapping motherboards)  :)

Thank you.  It worked!

I've been using Windows since it was first introduced.  I've never had to reassign com ports this way.  It used to be jumper settings on the physical card.

The problem is likely in the devices themselves. If a USB product doesn't have a unique number then Windows will assign the ports randomly at every start or when you plug / unplug. There is no way the OS (any OS) can check which device has been plugged into a specific port if it doesn't have some way to be indentified uniquely. In the software I write myself I always use serial port scanning to find specific devices so there is no reliance on exact port assignments.


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