I try to install som updates and get this error message:

W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...isty1_i386.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...isty1_i386.deb
Error reading from server. Remote end closed connection [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...eisty1_all.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...isty1_i386.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...isty1_i386.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...isty1_i386.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...eisty1_all.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...eisty1_all.deb
302 Moved Temp [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...isty1_i386.deb
Error reading from server. Remote end closed connection [IP: 91.189.88.45 80]


W: Failed to fetch http://archive.ubuntu.com/ubuntu/poo...tu1.1_i386.deb
302 Moved Temp [IP: 91.189.88.45 80]

After that I get this info:

Warning!
You are about to install software that can't be authenticated! Doing this could allow a malicious individual to damage or take control of your system.

Updates are:

gnome-btdownload, gnupg, gpgv, hal, hal-device-manager, lftp, libhal-storage1, libhal1, libpng12-0.

What to do???!

Maybe wait a few hours and then try an apt-get update/upgrade again? Or maybe switch mirrors? You definitely don't wanna install unauthenticated packages. What does your /etc/apt/sources.list look like?