This is usually caused by messing up the system’s Python with newer packages from PyPi (e.g. by executing easy_install –upgrade pip as root) and is not related to Isso at all.

Install Isso in a virtual environment as described in Interludium: Python is not PHP. Alternatively, you can use pip install –user to install Isso into the user’s home.

UnicodeDecodeError: ‘ascii’ codec can’t decode byte 0xff

Likely an issue with your environment, check you set your preferred file encoding either in LANG, LANGUAGE, LC_ALL or LC_CTYPE:

$ env LANG=C.UTF-8 isso [-h] [--version] ...

If none of the mentioned variables is set, the interaction with Isso will likely fail (unable to print non-ascii characters to stdout/err, unable to parse configuration file with non-ascii characters and to forth).

The web console shows 404 Not Found responses

That’s fine. Isso returns “404 Not Found” to indicate “No comments”.