Re: Lilypond-book not working after installing Python 3

[Joseph Wakeling]

Sven Siegmund wrote:
> Hello,
> 
> I work on Microsoft Windows 7 (64 bit), have MiKTeX 2.8 and lilypond
> 2.12.3 installed and lilypond-book worked fine until I installed
> Python 3.1.1.
> 
> Not knowing that Lilypond provides python 2.4.5 I was surprised that
> after I installed Python 3.1.1 and ran python, an older version of
> Python started. Then I realized it's python 2.4.5 from the
> \LilyPond\usr\bin directory. So I modified the PATH environment and
> moved the Python 3 path before the LilyPond\usr\bin path. Then the
> "python" command launched Python 3.1.1. So the minor python-launching
> problem looked like solved, but ...

Python 3.x is not guaranteed to be backwards compatible with Python 2.x,
and I don't think Lilypond has been ported to Python 3.  So you probably
do need to be running the earlier Python version with lilypond-book.

Why it should give an error after you changed the PATH back to what it
was before, I don't know... :-(