I am unable to install php5-dev package in ubuntu 12.10. I am getting the following on
sudo apt-get install php5-dev:
Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package php5-dev
I just tried installing php5-dev package in Ubuntu 12.10, and I didn't have any problems. It installed fine.
I'm including images of my software sources, just so you can compare with yours.
I also suggest the you just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below prior to installing:
I got a similar error when installing PHP or any other software. I changed the update server and then it started working.
So, please try to change the update server if you get a similar error.
You can change the update server you are using by going to System Settings > Software & updates, and then change the "Download from" line to another server.