Hello ,
Even I was getting the same error with MNE version 1.4. I use Windows 10 as my OS. I had to uninstall Conda and all its environments. I downloaded Anaconda again, as always, and tried to use:
conda install --channel=conda-forge --name=base mamba
mamba create --override-channels --channel=conda-forge --name=mne mne
but I get the error no environment named ‘mne’ present. Though the execution was complete.
Also, the MNE standalone installer link for Windows does not work. I am not sure what is wrong.