installation of untrusted packages... how to solve

What is the output of:

sudo apt-get update

Thanks

thanks

i have manage to uncheck some ppa, so i have install the updates, but after installation i cannot see my window borders to minimise or close the window any longer

Henry

Hi Good Morning

i tried to add some new ppa that i saw in ubuntu tweak, after adding the ppa, my home folder would not open agin, i lost my wireless network icon, my bluethoot icon, no starting up sound when you you start the computer.thunuderbird takes about fourty secounds to open firefox take about the same time to open, navigating in firefox takes a long time, lost my window border to minimise or close the window.

i gave an output

sudo apt-get update

 after the upgrade this is what am getting

Reading package lists... Done
W: GPG error: http://ppa.launchpad.net natty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY C5E6A5ED249AD24C

please kindly assist me

Henry

sudo apt-key adv --recv-key --keyserver keyserver.ubuntu.com C5E6A5ED249AD24C

You forgot to add the key for Deluge.