Usb Serial port not showing in windows 10 without rebooting

I have a few devices, photons and a electron. ive upgraded my laptop and im having problems with the USBserial1 port showing in device mananger.
If i plug it in it is detected and installed but i only have the one USB serial device available, unless i reboot the whole computer with the device attached then it will show both ports.
But then if i flash the device it resets and goes back to showing one port.
I can also get it to show both ports again if i uninstall the USB Composite device from device manager and rescan, but this is getting painful.
Ive tried a completly different laptop and also installing the standalone particle drivers from here: ( and the same thing occurs.
One thing thats the same between the 2 PCs ive tried is they both have the Intel USB 3.10 eXtensible Host Controller. My older laptop which worked flawlessly didnt have this.

Any ideas? I think ive tried every registry hack i can find and fiddling with Power options but nothing works. It seems like the second usb device starts up too slowly to be detected during the initial connection.

When, where and how are you activating USBSerial1 in your code?

You could try SYSTEM_THREAD(ENABLED) or placing your USBSerial1.begin() call into the STARTUP macro.

I suspect the activation of the auxiliary port happens after the USB negotiation is already completed and a deferred activation won’t re-trigger the “device connected” procedure to kick off another negotiation round.

Ok i added SYSTEM_THREAD(ENABLED) and thats fixed it. Odd i never had to use that before.

Maybe the (re)connection time got a bit longer for some obscure reason or your upgraded laptop does things quicker, resulting in the USB negotiation window to close before running setup().
In default running mode setup() only runs after the cloud connection has been established.

That makes sense, i think my old pc was USB2.0 spec so the new one probably has some other new funky things going on. Thanks for your quick help much appreciated.

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