It can not be upgraded

Legacy Netrunner 14.x
1

Hello!
Need some help please!
When i tried to upgrade the system i received following message:
Could not download packages
http://ppa.launchpad.net/netrunner-os/frontier-14-packages/ubuntu/dists/frontier-14/main/source/Sources
404 Not Found

http://ppa.launchpad.net/netrunner-os/frontier-14-packages/ubuntu/dists/frontier-14/main/binary-amd64/Packages
404 Not Found

http://ppa.launchpad.net/netrunner-os/frontier-14-packages/ubuntu/dists/frontier-14/main/binary-i386/Packages
404 Not Found

Can you help me please,what to do?
Thank you!

2

This topic has been discussed a few times already. You changed the sources.list with some kind of tool that did it wrong. Please change it back to the original state.
See this thread for example: http://forums.netrunner-os.com/showthread.php?tid=16365

3

Ok thank you