When Im trying to open or save a file in microsoft office 2007 using wine i get this file dialog with boxes that dont display. I use greek as my language .
Unfortunately, you're likely stuck with the top dialogue box, because WINE needs to have a save dialog that's aware of /, which the Windows native dialogue can't be. That said, you shouldn't have those squares popping up in place of characters. The first thing I'd try is installing Microsoft fonts.
https://help.zorin.com/docs/system-software/microsoft-fonts/
The next thing would be looking for a place in your WINE settings to install fonts as a dependency. Unfortunately, I use WINE only through Bottles, Steam, or other specific launchers that handle WINE configuration for me, so I'm not sure how one would go about this in your case. Winetricks is where I'd start looking, though.
Also wondering if it needs a language pack. Just ran a search and only leads to pirated software so no links. Do you really need Office 2007? You could use Free Office or Only Office instead if it is a compatibility issue.
