Access denied error when using WebUSB

[microbit-mark]

Win10
Chrome 68
firmware 0248

1. In Chrome Flash file via webUSB in makecode editor https://makecode.microbit.org/beta#editor?webusb=1
2. Open python.microbit.org/v/beta
3. Attempt to flash default file
4. Get access denied error
   

Resetting micro:bit doesn't resolve error
Unplug and replug micro:bit resolves error

@microbit-carlos @microbit-sam

Perhaps error message could be more descriptive?

[microbit-sam]

I can't get WebUSB to work in MakeCode at the moment to test

It looks like MakeCode is still connected to the micro:bit via WebUSB, so I think Chrome prevents the Python editor from connecting simultaneously. I'll see if I can reproduce later

[microbit-carlos]

I've had this before, and as you both mention is because MakeCode keeps that connection and the Python Editor gets rejected until the MakeCode tab is closed.
We could update the message displayed to ask if they have any other Chrome tab using WebUSB.

[microbit-mark]

I wondered if that might be the case. It seems to be a problem working the other way Python > Makecode too, but I could see it being handy for a teacher to have the two different editors open if you're showing how to do something in js blocks then in micropython.

[HoriLiu]

I had another error type in pythoneditor only:

MacOS 10.13.6
Chrome 69
firmware 0248

I had never open and connected WebUSB with the Makecode page:

1. Open python.microbit.org/v/beta
2. Press "Open REPL" <== 1st link OK
3. Attempt to flash default file
4. Get Bad preponse error
   
5. Press "Close REPL" ==> default file in programming zone
6. Press "Open REPL" ==> always blank in programming zone

Resetting micro:bit doesn't resolve error
Unplug and replug micro:bit then flash default file again, resolves the blank "Open REPL"

Open REPL function fail if user attempts to flash default file after "Open REPL".

[HoriLiu]

microsoft/pxt-microbit#1208
Maybe need to do timeout recovery after flashing has error.

[microbit-sam]

I think this is handled correctly now, can we close it?

Another process is connected to this device.
Close any other tabs that may be using WebUSB (e.g. MakeCode, Python Editor), or unplug and replug the micro:bit before trying again.

[microbit-carlos]

The fix for this has been deployed to beta.3: https://python.microbit.org/v/beta

I'll close this ticket, but if the error still persist please do reopen it.