I haven't checked in a while, since this is already set in my init.el file, but auxtex was using mkii/texexec a few years ago. Have you checked you're using mkiv/context?

On October 28, 2016 6:04:27 AM PDT, Fabrice Couvreur <fabrice1.couvreur@gmail.com> wrote:
I just upgraded to emacs24 and am having problems compiling my files who compiled perfectly with emacs23.
I installed AUCTeX with M-x-install package and that's it !
I deleted my old init.el file and start over !
The ~/.emacs.d only contains this :

fab @ debian: ~ $ cd .emacs.d /
fab @ debian: ~ / .emacs.d $ ls -l
total 8
drwx ------ 2 fab fab 4096 October 28 2:37 p.m. auto-save-list
drwxr-xr-x 5 fab fab 4096 October 28 2:26 p.m. ELPA
fab @ debian: ~ / $ .emacs.d

Consider the following file:
If I make a C-c C-c, all I get is the text in italics, the macro is not compiled.

% macros=mkvi

\definecolor[MyColorB][c=0.00, m=0.62, y=1.00, k=0.00]
\definecolor[MyColorA][c=0.00, m=0.10, y=0.20, k=0.00]




    path b ;
    picture p ;
    p := textext.rt("\white\Définition") ;
    p := p shifted (2BodyFontSize,OverlayHeight-ypart center p+.25ExHeight) ;
    b := boundingbox p leftenlarged .5EmWidth rightenlarged .5EmWidth ;
    fill OverlayBox withcolor \MPcolor{MyColorA} ;
    fill b withcolor \MPcolor{MyColorB} ;
    draw leftboundary OverlayBox ;
    draw p ;
    setbounds currentpicture to OverlayBox ;
\input knuth


%%% Local Variables:
%%% mode: context
%%% End:

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