Colomban,
I have found how to generate the encoding problem on a UTF-8 locale machine, so it isn't a windows only problem. Just specify the coding in the file, see attached (its filetype is none).
The OP has the problem because their machine locale is CP1252 so no coding needs to be specified but the problem is the same. [1][2][3]
Note the file will open fine, and the status line will show CP1252 but the menu document->set encoding->etc will show UTF-8.
If the file is opened as UTF-8 the double quotes shows wrong.
Cheers Lex
[1] http://thread.gmane.org/gmane.editors.geany.devel/5714 [2] http://article.gmane.org/gmane.editors.geany.general/6285 [3] https://sourceforge.net/tracker/?func=detail&aid=3509407&group_id=15...