This error message has been annoying the hell out of me anytime I try and do anything with my packages on my Ubuntu server:
subprocess post-removal script returned error exit status 2
Following the instructions at http://www.cyberciti.biz/tips/troubleshooting-debian-ubuntu-package-upgrades-removals.html (expect that I had to comment out the line set -e with a # and hey presto package installation and removal works again!
Phew. Sometimes Linux still requires hacking about – but I guess at least you can get in there and fix things once you know how – unlike the dll-registry hell / black box of Windows!