Comment 4 for bug 653571

Actually https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/834480 it's not really a duplicate as it's talking about a different version of Ubuntu. This bug report is for version 10.10, the other is for alpha Oneiric Ocelot (11.10). :)

I had the same bug with a nightly build. When I selected any of the checkboxes Third party software or Download updates while installing I could not install. I had to boot cd again and then start the installation without those checkboxes for the installer to work.