Comment 7 for bug 1290217

Hi!

I had the same issue and in my case I fixed with the following steps:
(previous these steps I purged sendmail because I needed only postfix)

- searched all the remains of sendmail and removed from the places that I thought it would affect the boot process
- on /etc/network/interfaces I deleted all the other lines added before - there remained only 2 lines (default ones)
- purged the network-manager (but before I saved all the needed packages for a reinstall from an USB stick - .deb files)
- added packages: plasma-nm, plasma-widget-networkmanagement, network-manager-gnome
- checked all the remained errors from /var/log/upstart/ logs - in my case there were none left after reboot