can nt update ubuntu

[ewientje]

Hi, Iḿ new to ubuntu, just installed ubuntu, and after trying to update , I get the following message, What am I doing wrong.

W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used.GPG error: http://ppa.launchpad.net intrepid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 60D11217247D1CFF

W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used.GPG error: http://ppa.launchpad.net intrepid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6AF0E1940624A220

W: Failed to fetch http://ppa.launchpad.net/openoffice-pkgs/ubuntu/dists/intrepid/Release

W: Failed to fetch http://ppa.launchpad.net/tualatrix/ubuntu/dists/intrepid/Release

W: Some index files failed to download, they have been ignored, or old ones used instead.

[albandy]

You've modified the repositories with launchpad entries.
Go to synaptic and disable the third party repositories you've added

[ewientje]

I have never modified the repositories with launchpad. Don t know what they are, and where to find them. And what is synaptic ?
Iḿ kind of new to Linux, so ??

[albandy]

please, open /etc/apt/sources.list and paste the contents here.

[ewientje]

I reinstalled Ubuntu with another iso, and now I can update, so the problem is solved.
Thank you all for your help.

[Neo_The_User]

heh reinstall works too.