I am attempting to install 12.04 from a 4GB flash drive. I installed the .iso file using Universal USB Installer, no problems. I restarted my computer and the Ubuntu installer booted just fine, so I went through the steps up to choosing installation options of either dual boot or replacing Windows (I am running Windows 7). I selected dual boot and the installer said it would restart to continue the install process. When it restarted, it went right back to the first installation step, not saving any of my progress. I checked for damaged files and came back with 3 corrupted files. I re-downloaded Ubuntu 12.04, re-installed on my flash drive, and tried again, only to get the exact same result. Any suggestions?