I own a second notebook (my old one) which currently runs Debian stable. I use it for skype only, as I don’t want this proprietary software on my main machine. Recently, I deinstalled a lot of crap which comes with Debian per default (in the Gnome version). I deinstalled Libreoffice. I deinstalled Gimp. I deinstalled similar software nobody needs (on a skype-only machine).
Suprisingly I deinstalled network-manager as well. I don’t know how this could happen! Now, how to reinstall the network-manager if you cannot access the internet? Well, if you did not reboot, it might work. But I did! It’s really simple: Just go to the Debian-packages website and download the package. Then, transfer it to the appropriate machine and install it with
sudo dpkg -i package
Well, you can only do that if you have another machine where you can download the package. If you don’t have such a machine, you should ask a friend or so! If you didn’t run
sudo apt-get autoremove
The package may be remaining in the cache of
apt-get. You have to google
around where this cache is, but the procedure should be the same, if you found