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naylor@naylor-desktop:~$ sudo dpkg -i --force-all /var/cache/apt/archives/ttf-op*
(Reading database ... 120168 files and directories currently installed.)
Preparing to replace ttf-opensymbol 2.0.4-0ubuntu4 (using .../ttf-opensymbol_2.0.4-0ubuntu4_all.deb) ...
Unpacking replacement ttf-opensymbol ...
Setting up ttf-opensymbol (2.0.4-0ubuntu4) ...
Updating fontconfig cache...
"/usr/share/fonts": error scanning
"/usr/share/X11/fonts": error scanning
"/usr/local/share/fonts": error scanning
"/var/lib/defoma/fontconfig.d": error scanning
dpkg: error processing ttf-opensymbol (--install):
 subprocess post-installation script returned error exit status 4
Errors were encountered while processing:
 ttf-opensymbol
naylor@naylor-desktop:~$