Windows 10: COM3 COM4 ports missing

I have posted this thread in General support but now I think this section may be better.

WINDOWS 10
I am working it with Arduino microcontrollers connecting them via ports com3 or com4.
I had a random problem where half of the time communication did not work. I was receiving semaphore time out problems.
The problem was usually going away after the series of restarts. I was trying to find a permament fix. I thought there is something wrong with COM3 and COM4 settings. I tried to delet and install them anew and now I don't see them anymore. And have no clue how to fix it.
In Control Panel automatic scan for new hardware is not detecting them.
I am including two screenshots to describe my dilema.
I managed to somehow enable the communication to work on COM4 last night.
Now as you can see I see no COM3 COM4 in Control Panel but when I list the list of ports it shows COM4 as Busy.

Any help would be greatly appreciated

:)

 

Bluetooth coms fail with duplicate com3 port

After further testing it would appear that if I create an incoming At Serial port manually then the instrument will connect and transfer data, which is a significant improvement.

However the process is not straight forward -:

Start app & Check ports => 1x com3

Open settings => bluetooth and other devices.

Pair instrument

check "Bluetooth settings" > com ports (Com3 & Com4)

Check ports in app: 2xcom3 and 1x com4

Try to connect from app=> none of ports will connect

go to "Bluetooth settings" & delete all com ports (1xcom3 and 1x com4)

Create incoming port => creates 1x com3 incoming serial.

Goto app => displays 2xcom3

App connects using first com3

I will try to streamline this.

The pairing process clearly does not create com ports that work. But why should a manually-created port work?

 

Bluetooth coms fail with duplicate com3 port

OK, I can make a connection but there are com ports left in the wake of the process which dont work and which have to be removed by hand... and that includes editing the registry - so that can't be right.

So I am back asking the question what is happening in the sequence below which is not supposed to be... and why is that? Appologies but it's a hell of a long process to get to the errors - but that's what Ive been left fighting with...

The instrument is called a Kane

The aim of this testing is to see if the PC and Kane can be turned on, connected, turned off, turned on and connected again - without fuss. On my old XP pc I can do this successfully all day. With my win10 PC I have to edit the registry...

Unpair device

Com ports disappear from BT Settings

Regedit

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\COM Name Arbiter = 0

Computer\HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\SERIALCOMM shows 2xcom3 (which must be wrong...?)

Delete 2x com3

Reboot

Switch on Kane

Run app

No com ports

connect

no com ports

Devices and printers (this has worked in the past)

Add device

No Kane

BT & Other devices

Add BT device

Select Kane

connect

2x connection msgs

Done

More BT options

com ports tab

Note com3 & com4 AT serial

App

select com4

connect

success

save data

success

disconnect

close

shut down Kane

reboot pc

log in to pc

Switch on kane

BT & other devices

More BT options

Settings

com ports

Note com3 & com4 AT serial

cancel

select kane

dialogue shows "paired"

App

com3 & com4 available

select com4

connect

add device msg from windows

add

Dialogue shows "connection failed..." WHY?

BT & other devices

More BT settings

delete com3/4

add com3 outgoing AT serial

app

only com3 showing

select com3

connect

select "add"

Pair device msg - connection failed - WHY?

close

BT & other devices

select Kane and unpair

Select add bt device

select kane

connect

dialogue shows "paired"

BT settings show com3 AT serial and com4

app

now 2xcom3 +com4

select both com3s in turn and get "Port not functioning" for both, WHY?

I can now begin at the top of this process and edit the registry to remove the duplicate com ports.

 

Unable to assign "new outgoing port" to Com4

I am working with an Intermec CN3 running WinMo5. I have an external printer attached to the device via BlueTooth using Com4 as the outgoing port. I switch out the old printer with a new one. Windows Mobile will not release the Com port for me to
use with the new printer. Everything has been removed, BT was turned off/on and the PDA reset. Com4 is still showing as in use. How can I force WinMo to release the Com port? I am not sure what else I can try.



Thank you.