After updating MikTex up to 09.04.2018 (MikTex 2.9.6637, Win 10, 64bit) I've got the error:

*geometry* detected driver: pdftex
! LaTeX Error: \chapterformat undefined.
See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
l.29 \begin{document}

Maybe somebody knows how to fix it?

Sorry, my bad. This is MWE:





I use XeLatex and without


everything compile without errors.

  • As far as I can see, \chapterformat is defined in the Komascript classes. Which document class are you using?
    – egreg
    Apr 9, 2018 at 13:42
  • @egereg I'm using extreport: \documentclass[a4paper,14pt]{extreport}
    – Alexey
    Apr 9, 2018 at 13:44
  • 2
    Show a complete minimal example. Apr 9, 2018 at 13:45
  • 2
    That is why you should always provide an example document, no one could guess from your question which document class you use. Also your wording implies that something changed after the update but extreport has never defined that command. Apr 9, 2018 at 13:49
  • 1
    If you remove interfaces-base, the error disappears. The package is aimed to ease doing settings for various packages and you don't seem to be using its features. Avoid it.
    – egreg
    Apr 9, 2018 at 15:22

1 Answer 1


The interface-base package should not be loaded alone, but accompanied by \LoadInterface instructions.

Just remove it, as you don't seem to be using its features (and it also appears to be buggy).

  • Unfortunately, I use some \LoadInterface instructions. Maybe you know how to fix interface-base.sty?
    – Alexey
    Apr 9, 2018 at 15:34
  • @Alexey No. I don't use FC's packages and I don't recommend using them.
    – egreg
    Apr 9, 2018 at 15:36
  • Ok. New version of polyglossia (08/04/2018) can't work with interface-base.sty
    – Alexey
    Apr 9, 2018 at 16:27

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .