# How to change default font for all existing notebooks at once?

By default, Mathematica 9 and 10 use Gill Sans MT fonts for headings of title/subtitle/section/subsection/subsubsection. Unfortunately, Gill Sans MT fonts have no Cyrillic letters, so that all headings in my old notebooks have become corrupted. I found one remedy. After uninstalling Gill Sans fonts from OS, Mathematica substitutes the absent fonts with something else which turns out to have Cyrillic letters.

Is there a less radical solution?

Setting individual stylesheets for every notebooks (as explained here) is not an option for me.

• The combination of 11766 and 9942 should largely solve your problem. – bbgodfrey Dec 30 '15 at 13:36
• Out of curiosity, which operating system were you on? – John Fultz Dec 31 '15 at 2:20
• @JohnFultz: I observed this problem on Windows 7/8.1/10. – Igor Kotelnikov Dec 31 '15 at 21:16

SetOptions[\$FrontEnd, StyleHints -> {"CodeFont" -> "Courier"}]