I installed 'unifi-beta' in Ubuntu server 15.04.
At the end of the installation process something went wrong.
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Setting up unifi-beta (4.6.3-4850) ...
Failed to start unifi.service: Unit unifi.service failed to load: No such file or directory.
dpkg: error processing package unifi-beta (--configure):
subprocess installed post-installation script returned error exit status 6
Setting up icedtea-6-jre-cacao:amd64 (6b35-1.13.7-1ubuntu1) ...
Setting up icedtea-6-jre-jamvm:amd64 (6b35-1.13.7-1ubuntu1) ...
Setting up openjdk-6-jre-lib (6b35-1.13.7-1ubuntu1) ...
Processing triggers for libc-bin (2.21-0ubuntu4) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for systemd (219-7ubuntu3) ...
Processing triggers for ca-certificates (20141019) ...
Updating certificates in /etc/ssl/certs... 0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d....
done.
done.
Errors were encountered while processing:
unifi-beta
E: Sub-process /usr/bin/dpkg returned an error code (1)
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When I tried 'sudo apt-get remove unifi-beta' I get this:
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Do you want to continue? [Y/n]
Setting up unifi-beta (4.6.3-4850) ...
Failed to start unifi.service: Unit unifi.service failed to load: No such file or directory.
dpkg: error processing package unifi-beta (--configure):
subprocess installed post-installation script returned error exit status 6
Errors were encountered while processing:
unifi-beta
E: Sub-process /usr/bin/dpkg returned an error code (1)
------------------------------------------------------------

'dpkg -l unifi-beta' gives: rF unifi-beta 4.6.3-4850 all Ubiquiti UniFi server

Question is - how to get rid of the package 'unfi-beta' - I have tried all aptitude & apt-get commands

*

# apt-get install -f

No - it doesn't work ...

sudo apt-get install -f
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up unifi-beta (4.6.3-4850) ...
Failed to start unifi.service: Unit unifi.service failed to load: No such file or directory.
dpkg: error processing package unifi-beta (--configure):
subprocess installed post-installation script returned error exit status 6
Errors were encountered while processing:
unifi-beta
E: Sub-process /usr/bin/dpkg returned an error code (1)