Migrating from makecode v7.0.20 to 8.07

I am having problems migrating code written for MicroBit from:
makecode.microbit.org version 4.0.24
Microsoft Makecode version 7.0.20
Microbit runtime version 2.2.0-rc6
codal-microbit-v2 runtime version 0.2.35

makecode.microbit.org version 5.0.12
Microsoft Makecode version 8.0.7
Microbit runtime version 2.2.0-rc6
codal-microbit-v2 runtime version 0.2.40

It seems all the code written that uses some kind of extension libraries are having problems but I do not get any specific message showing the errors.
Pop up screen shows:
Extension Errors
Looks like there are some errors in the extensions added to this project. How would you like to proceed?
Try to fix
Ignore errors and open

Using either options does nothing to resolve the issue.
Durling load it just goes in the loop (on the simulator side of the screen).
I also searched the whole drive and can’t find the corresponding .hex files anywhere. I also searched the registry - no luck.
So the code is stored somewhere but where?
I also downloaded the new version of makecode (I have both versions on my windows 10 latest version).
When I try to save the code into a file from the old version of MC and try to load it into the new version of MC most of the code (99%) disappears and is not loaded.
Any idea what’s the best way to preserve all the codes I have written and migrate it into new version of MC or how to diagnose the error that is preventing me to load the code?
I had not used makecode in over 2 years but I can’t afford to re-write all that that code.
while trying to resolve this…I just realized, some of the code has been lost. Using undo (at the bottom right hand side) does nothing. This happened when I tried to reload the code and use the “fix it” option in the old version. Now when I load that project - all the code is gone.

Any help would be appreciated.

You might try:

  1. Open two windows with MakeCode side-by-side
  2. Open the existing project in one.
    a. Slide the switch to the JavaScript view
  3. Open a new project in the other.
    a. Add all the extensions used in the existing project
    b. Slide the switch to the JavaScript view
    c. Use copy/paste to copy the code from the existing project into the new one’s window.
    d. See if there are specific lines/errors highlighted. If so, try to fix them one-by-one. (You can switch back to the Blocks view and work with Blocks rather than JavaScript).

Hello Bsiever,

Thanks for your detailed response.

I’ll try out the suggested solution over the weekend and report back on the outcome.

Greatly appreciate your help.

Kind regards,


Hello Bsiever,
So here is the situation:
I have two versions of offline MC (V4 and V5). All my projects/code is only visible in the offline V4 MC (since the .hex files were not saved on disk).
I also have the urls for V3, V4 and V5 (latest) of MC for online use.
None of these can see the projects.
I have around 400 projects. 200 or so were last modified 2 years ago, 6 in the past few mins to a max of 4 days ago and the rest 3 years ago.
Of the 6 touched in the last 4 days max, I have lost the code of most projects (that had extensions) when I tried to load it using Offline MC V4 (OMC4). For example the project in which I had used BME280 (dust sensor) and extension for RTC (real time clock) and ESP8266 (basically a project to measure air quality) and send the data to ThingSpeak portal for plotting the data. 99% of the code is gone when I try to load the project.
So, unfortunately, the solution you propose is not working for me - as the code is getting lost at load time.
Greatly appreciate your help though. I have also opened a ticket with the microbit education team as well and Martin is working on it.