Hello,

Henrik Frisk <frisk.h@gmail.com> writes:

> I have been trying out ob-lilypond and it works really well, except for the
> arrange mode. Any attempt to run ly-tangle results in 'Symbol’s function
> definition is void: org-babel-get-header' and so does an attempt to export
> a file, such as the example file, in basic mode to html for instance.
>
> I was thinking it was related to sh/shell since this appears to be a common
> issue with regard to this error, but the ob-lilypond does not appear to use
> any reference to sh (the doc for ob-lilypond does). I also tried to load
> ob-core as was suggested in some post but that didn't work either.
>
> Other tangle other languages works fine.
>
> Any suggestions?

`org-babel-get-header' was removed in Org 9.0 and current ob-lilypond.el
doesn't call this function. My guess is you are mixing a new Org release
with an old "ob-lilypond.el".