If you set up a local diversion as instructed in the section "Renaming ack-grep on Debian-derived distros" on their website, remove it:
sudo dpkg-divert --remove /usr/bin/ack-grep -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1385390 Title: package ack-grep 2.12-1 failed to install/upgrade: trying to overwrite `/usr/bin/ack', which is the diverted version of `/usr/bin/ack-grep' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ack-grep/+bug/1385390/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
