Ubuntun 15.10 mit Unity.

Der Versuch den KDE-desktop zu installieren schien erfolgreich. KDE-Desktop startet allerdings nicht. Der Versuch den KDE-desktop wieder zu deinstallieren gelang nicht - Rechner hängte sich auf. Nach Neustart und Start des 'SoftwareCenters' kommt folgende Fehlermeldung:


(Reading database ... 70%
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(Reading database ... 366058 files and directories currently installed.)
Preparing to unpack .../kde-config-telepathy-accounts_4%3a15.08.2-0ubuntu1_amd64.deb ...
Unpacking kde-config-telepathy-accounts (4:15.08.2-0ubuntu1) ...
dpkg: error processing archive /var/cache/apt/archives/kde-config-telepathy-accounts_4%3a15.08.2-0ubuntu1_amd64.deb (--unpack):
 trying to overwrite '/usr/share/accounts/services/google-im.service', which is also in package account-plugin-google 0.12+15.10.20150723-0ubuntu1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Selecting previously unselected package kde-telepathy-minimal.
Preparing to unpack .../kde-telepathy-minimal_15.04.20ubuntu1_all.deb ...
Unpacking kde-telepathy-minimal (15.04.20ubuntu1) ...
Errors were encountered while processing:
 /var/cache/apt/archives/kde-config-telepathy-accounts_4%3a15.08.2-0ubuntu1_amd64.deb
Error in function: 
dpkg: dependency problems prevent configuration of kde-telepathy-minimal:
 kde-telepathy-minimal depends on kde-config-telepathy-accounts (>= 15.04.0); however:
  Package kde-config-telepathy-accounts is not installed.

dpkg: error processing package kde-telepathy-minimal (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of kde-telepathy:
 kde-telepathy depends on kde-telepathy-minimal (= 15.04.20ubuntu1); however:
  Package kde-telepathy-minimal is not configured yet.

dpkg: error processing package kde-telepathy (--configure):
 dependency problems - leaving unconfigured


Auch ein: "sudo dpkg --purge --force-all kde-telepathy-minimal"
brachte keinen Erfolg. Wie kann ich die Paketdatenbank reparieren?