Thank you, I did not think about that. It helped a lot! I found out that the problem causing the unicode error was, that only the 'python' command was set up on my windows machine, but not the 'python3' command. This was the exact error for documentation:

DEBUG:clearml_agent.commands.worker:Searching for python3
Traceback (most recent call last):
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\helper\process.py", line 204, in normalize_exception
    yield
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\helper\process.py", line 245, in call_subprocess
    return func(list(self), *args, **kwargs)
  File "C:\Users\User\AppData\Local\Programs\Python\Python310\lib\subprocess.py", line 421, in check_output
    return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
  File "C:\Users\User\AppData\Local\Programs\Python\Python310\lib\subprocess.py", line 526, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['python3', '--version']' returned non-zero exit status 9009.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\commands\worker.py", line 3269, in install_virtualenv
    self.find_python_executable_for_version(requested_python_version)
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\commands\worker.py", line 3078, in find_python_executable_for_version
    output = Argv(executable, "--version").get_output(
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\helper\process.py", line 192, in get_output
    self.call_subprocess(subprocess.check_output, *args, **kwargs)
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\helper\process.py", line 244, in call_subprocess
    with self.normalize_exception(censor_password):
  File "C:\Users\User\AppData\Local\Programs\Python\Python310\lib\contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "C:\Users\User\venvs\clearml\lib\site-packages\clearml_agent\helper\process.py", line 210, in normalize_exception
    e.output = e.output.decode()
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xfc in position 38: invalid start byte