Mamba stopped working on Win10

[btvd]

Hey, community! Recently I've encountered such behavior of mamba:

No mapping for the Unicode character exists in the target multi-byte code page.

>>>>>>>>>>>>>>>>>>>>>> ERROR REPORT <<<<<<<<<<<<<<<<<<<<<<

Traceback (most recent call last):
  File "C:\ProgramData\Anaconda3\lib\site-packages\conda\exceptions.py", line 1129, in __call__
    return func(*args, **kwargs)
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\mamba.py", line 935, in exception_converter
    raise e
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\mamba.py", line 928, in exception_converter
    exit_code = _wrapped_main(*args, **kwargs)
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\mamba.py", line 886, in _wrapped_main
    result = do_call(parsed_args, p)
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\mamba.py", line 756, in do_call
    exit_code = update(args, parser)
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\mamba.py", line 646, in update
    return install(args, parser, "update")
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\mamba.py", line 258, in install
    init_api_context(use_mamba_experimental)
  File "C:\ProgramData\Anaconda3\lib\site-packages\mamba\utils.py", line 197, in init_api_context
    api_ctx = api.Context()
RuntimeError: No mapping for the Unicode character exists in the target multi-byte code page.

$ C:\ProgramData\Anaconda3\Scripts\mamba upgrade --all -c conda-forge

I do not understand where it came from. Just updated to newer version. I've been working with mamba 1 year and this is first time when I see such thing. Please, can you recommend me what to do? I've tried to conda remove / uninstall mamba - but no luck (could not uninstall, very long time of solving). I've tried to re-install - no luck (it just says that all needed packages is there, but mamba throws the same error) . Need your help.

I use:

mamba 0.27.0 conda 22.9.0 Win10 Python 3.9.13 in base (3.10.* in other envs)

[jonashaag]

The easiest way to reinstall would be to remove Conda entirely (delete all the folders from your computer) and then install Mambaforge.

[btvd]

The easiest way to reinstall would be to remove Conda entirely (delete all the folders from your computer) and then install Mambaforge.

How can I save my env to use it after re-install? Because I use it for work... I could delete base, but not working env... I hope that there is another way to get out of this situation.

[jonashaag]

I'm not saying you should do this but you can try something like

mamba env export -n yourenv --from-history > environment.yml

which will create an environment.yml file from the explicitly installed packages in your env. Then you can just use mamba env create -f environment.yml to reinstall the env. It is good practice to be able to reproduce your env anyways, so not only using mamba install somepkg, but having an environment.yml.

[btvd]

Thank you for advice! I have not done this before. Tried to create yml file but could not even locate it on Win10. Where mamba stores such files?

[jonashaag]

You use the command above to create the yml file.

[btvd]

Where is this file stored on Win10? I could not find it and check if it created? Still I want to understand the nature of the error in my first post. So If someone can explain why it happen to my system and what should I do to have no errors like: "No mapping for the Unicode character exists in the target multi-byte code page." - will be very grateful!

[jonashaag]

It is stored in the folder where you execute the command.

Assuming that you are using bash:

pwd  # eg. /C/Users/abc/
mamba env export -n yourenv --from-history > environment.yml  # /C/Users/abc/environment.yml

I guess it works the same way in PowerShell but I'm not sure. See eg. https://askubuntu.com/questions/420981/how-do-i-save-terminal-output-to-a-file

[btvd]

I've just deleted mamba and returned to conda on WIn10, which works slow, but works... Until it's understood what happed to mamba with recent updates...