Good evening. I just installed Ubuntu 12.04 using a USB, but right after the install, after restarting the machine, I get a message asking me to insert a bootable drive. My boot settings in Bios have the hard drive first, then DVD, then USB stick, and I have two systems installed, Windows 7 and Ubuntu 12.04. I suspected the hard drive got somehow disconnected internally, so I checked but everything was in place. I used the live USB to start Ubuntu, and I could see the hard drive and mount whatever partition I wanted. The one that contains the recently installed Ubuntu, looks the same. (It hasn't been deleted or anything). I'm not sure if this is a hardware problem or a loader(grub) problem, because the hard drive is visible. Only it isn't seen by the BIOS. My only means of internet connection is a USB modem, which doesn't work when I'm using the live USB, so I have can't download anything from the internet, in case someone asks. I also reinstalled Ubuntu 12.04, to no avail. This is my second problem with this laptop, and Ubuntu, and it's not even a week old. I hope this one gets solved. Thank you.