Installing 0.9.31 messes with file types in Ubuntu

[lof]

I recently upgraded my old 0.9.27 to 0.9.31 (interesting bugfix for my Nook Color) on my old Ubuntu Lucid and not only did calibre stopped working (and was nowhere to be found although install proceeded without a hitch) but it messed with many filetype association.

All epub and mobi and pdf and video files were changed to Text/plain.

I have been trying to revert to 0.9.30 then 0.9.29 and now 0.9.27 following the instructions, but to no avail.

Please advise.

[kovidgoyal]

1) calibre does not change file type associations

2) calibre will be installed wherever you asked the install script to install it, by default, /opt/calibre

3) You can always run calibre by running the command calibre in a terminal, which the install script tells you at the end of the installation procedure.

[lof]

For whatever reason no error message during install

Downloaded 57157522 bytes 
Checking downloaded file integrity... 
Extracting files to /opt/calibre ...
Extracting application files... 
Creating symlinks...
	Symlinking /opt/calibre/fetch-ebook-metadata to /usr/bin/fetch-ebook-metadata
	Symlinking /opt/calibre/lrf2lrs to /usr/bin/lrf2lrs
	Symlinking /opt/calibre/ebook-convert to /usr/bin/ebook-convert
	Symlinking /opt/calibre/ebook-meta to /usr/bin/ebook-meta
	Symlinking /opt/calibre/lrfviewer to /usr/bin/lrfviewer
	Symlinking /opt/calibre/calibre to /usr/bin/calibre
	Symlinking /opt/calibre/markdown-calibre to /usr/bin/markdown-calibre
	Symlinking /opt/calibre/calibre-debug to /usr/bin/calibre-debug
	Symlinking /opt/calibre/calibre-parallel to /usr/bin/calibre-parallel
	Symlinking /opt/calibre/web2disk to /usr/bin/web2disk
	Symlinking /opt/calibre/calibre-server to /usr/bin/calibre-server
	Symlinking /opt/calibre/calibre-customize to /usr/bin/calibre-customize
	Symlinking /opt/calibre/ebook-polish to /usr/bin/ebook-polish
	Symlinking /opt/calibre/ebook-viewer to /usr/bin/ebook-viewer
	Symlinking /opt/calibre/calibre-smtp to /usr/bin/calibre-smtp
	Symlinking /opt/calibre/lrs2lrf to /usr/bin/lrs2lrf
	Symlinking /opt/calibre/ebook-device to /usr/bin/ebook-device
	Symlinking /opt/calibre/calibredb to /usr/bin/calibredb
Setting up command-line completion...
Installing bash completion to /etc/bash_completion.d/calibre
Setting up desktop integration...

but calibre is nowhere to be found. Seems even /opt has disappeared. So running calibre from terminal only prompts for apt-get install calibre.

I am pretty sure the calibre upgrade was the only thing I changed during the time I noticed this issue. I know I can't blame calibre for all the mess - I am using a now unsupported system - but if someone could offer some quidance on what could have gone so wrong it would help me fix my machine.

[kovidgoyal]

If /opt has disappeared you have serious problems, likely filesystem corruption/hard disk failure.

[theducks]

/opt MIA ?

maybe your user rights got messed up

sudo ls -l /

[lof]

total 172
drwxr-xr-x   2 root root  4096 2012-10-04 23:04 bin
drwxr-xr-x   3 root root  4096 2013-05-17 23:57 boot
drwxr-xr-x   2 root root  4096 2011-05-18 19:22 cdrom
drwxr-xr-x  17 root root  3760 2013-05-28 08:23 dev
drwxr-xr-x 153 root root 12288 2013-05-28 08:23 etc
drwxr-xr-x   4 root root  4096 2010-04-23 12:11 home
lrwxrwxrwx   1 root root    33 2013-05-17 23:57 initrd.img -> boot/initrd.img-2.6.32-47-generic
lrwxrwxrwx   1 root root    33 2013-03-23 19:06 initrd.img.old -> boot/initrd.img-2.6.32-46-generic
drwxr-xr-x  22 root root 16384 2013-04-10 16:01 lib
drwx------   2 root root 16384 2011-05-18 19:20 lost+found
drwxr-xr-x   7 root root  4096 2013-05-23 08:54 media
drwxr-xr-x   3 root root  4096 2012-12-20 14:39 mnt
drwxr-xr-x   8 root root  4096 2013-05-20 16:50 opt
dr-xr-xr-x 151 root root     0 2013-05-28 08:23 proc
drwx------  16 root root  4096 2013-04-30 21:17 root
drwxr-xr-x   2 root root  4096 2013-04-10 16:01 sbin
drwxr-xr-x   2 root root  4096 2009-12-05 22:55 selinux
drwxr-xr-x   3 root root  4096 2011-10-19 00:47 srv
drwxr-xr-x  12 root root     0 2013-05-28 08:23 sys
drwxrwxrwt  18 root root 73728 2013-05-28 15:05 tmp
drwxr-xr-x  13 root root  4096 2011-05-27 11:59 usr
drwxr-xr-x  15 root root  4096 2011-02-11 14:20 var
lrwxrwxrwx   1 root root    30 2013-05-17 23:57 vmlinuz -> boot/vmlinuz-2.6.32-47-generic
lrwxrwxrwx   1 root root    30 2013-03-23 19:06 vmlinuz.old -> boot/vmlinuz-2.6.32-46-generic

The rights for /opt still exist but I guess it has something to do about disc corruption as Kovid mentioned, although SMART tests are ok. Could there be a conflict between calibre libraries and mime-database?

Some other Ubuntu 10.04.4 user got the same issue but couldn't get proper answers that's why I thought it was more of an upgrade issue
http://askubuntu.com/questions/29272...-mime-database

Thanks a lot for your thoughts.