[Trisquel-users] I deleted Courier 10 Pitch, and broke FontForge

[LDrumbler]

I no longer want the font Courier 10 Pitch, so I opened a file manager as  
root and deleted it from /usr/share/fonts. But now when I try to open a font  
in FontForge, the window briefly appears and then quits. When I went to the  
terminal from which I'd run gksu thunar, I noticed several messages like  
this:

Help! Server claimed font
        -bitstream-courier 10 pitch-medium-r-normal--16-0-0-0-m-0-iso10646-1
 existed in the font list, but when I asked for it there was nothing.
 I may crash soon.
Segmentation fault


How can I fix this? Where in the system is this command given, so that I can  
prevent this crash from occurring.