package libatk-adaptor-schemas 2.4.0-1ubuntu2 failed to install/upgrade: trying to overwrite '/usr/share/glib-2.0/schemas/org.a11y.atspi.gschema.xml', which is also in package libatk-adaptor 2.2.1-0ubuntu1
After normal upgrade to 12.04 did not upgrade kde, I manually did the update, upgrade cycle only to be prompted to do an apt-get -f install. Doing that resulted in error notices about xmind having a blank line in its Description. After fixing that, in both pkgs and available, the upgrade cycle completed. The reboot then showed my desktop without wallpaper or my usual programs list, but at least with an applications list I could choose from.
The first reboot after the manual upgrade tried to report a dbus problem which has no coherent google-able useful report. But that did not recur on the second reboot, which then yielded this error.
DistroRelease: Ubuntu 12.04
Uname: Linux 3.2.0-24-generic x86_64
Date: Thu Apr 26 20:38:40 2012
dpkg: error processing /var/cache/
trying to overwrite '/usr/share/
ErrorMessage: trying to overwrite '/usr/share/
Title: package libatk-
UpgradeStatus: Upgraded to precise on 2012-04-26 (0 days ago)