Pyenv-win uses https://www.python.org/ftp/python/ as the default mirror; see mirrors.txt. It appears that the PSF has removed PyPy versions from this directory. I see a list of all of the official PyPy releases at https://buildbot.pypy.org/mirror/, but I don't think that pyenv-win can handle these because it assumes that the download will be an EXE or MSI file (among other lesser reasons). I can't find a mirror for installers. I wonder why PSF removed the PyPy installers from that directory. In any case, because of the PSF's change, this project needs to be updated to pull from multiple mirrors (or least use an additional mirror to determine the availability of versions at https://downloads.python.org/pypy/ (though they won't necessarily always be in sync)).