I've a problem with my LibreOffice. Using an old archive that I have (with the Maxwell's equations), the greek letters are like squares. I tried to change something in the alphabet but even the font don't have any greek letters (they appear like squares too), both Greek and iGreek letters package. Sounds like a packet that isn't installed or corrupted, but I still redownloaded and reinstalled the LO and I don't know whose I have to install. With the OO my equations worked well (I made the file with it). What am I supposed to do?