[Koha] E: Sub-process /usr/bin/dpkg returned an error code (1)

[Vimal Kumar V.]

Dear Friends,
I got following error try to install Koha 3.18.


root at ubuntukoha:/home/koha# apt-get install koha-common
Reading package lists... Done
Building dependency tree
Reading state information... Done
koha-common is already the newest version.
The following package was automatically installed and is no longer required:
  libjs-yui
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]? y
Setting up koha-common (3.18.06.3) ...
install: invalid user `library-koha'
Upgrading database schema for library
unable to locate Koha configuration file koha-conf.xml at
/usr/share/koha/lib/C4/Context.pm line 373.
unable to locate Koha configuration file koha-conf.xml at
/usr/share/koha/lib/C4/Context.pm line 373.
unable to locate Koha configuration file koha-conf.xml at
/usr/share/koha/lib/C4/Context.pm line 373.
Can't call method "config" on unblessed reference at
/usr/share/koha/lib/C4/Context.pm line 779.
dpkg: error processing koha-common (--configure):
 subprocess installed post-installation script returned error exit status
255
Errors were encountered while processing:
 koha-common
E: Sub-process /usr/bin/dpkg returned an error code (1)


May I know the reason behind the error?
Regards,
-- 
Vimal Kumar V.
Technical Assistant
Mahatma Gandhi University Library
Kottayam, Kerala- 686 560
Web: http://www.vimalkumar.info
Blog: http://linuxhalwa.blogspot.com http://kohageek.blogspot.in
http://moovandan.blogspot.in
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