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I am trying to come back to Linux after switching computers, but am having trouble installing Ubuntu. The external hard drive works with universal usb installer (including preformatting it to FAT32), but when I try to boot it it says that it is missing an OS. I even tried using my flash drive to install it on the internal hd and the external hd, but neither worked. -Thanks for even reading my essay, bayf

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Have you installed it as a liveUSB or as an actual install? –  Hashken Mar 21 '14 at 4:26
My first try was as to use a live usb to do a full install on the hdd, but the hdd did not boot and then I tried to make the hdd the live usb and install on itself, but then it said "missing operating system". Finally, I tried to install it on the internal hd (did not want to but just tried to test it) and that did not work b/c I could not make the Windows unallocated space free space, it listed it as unusable. –  bayf Mar 21 '14 at 4:38
Ok. When you try to do a full install on an external hard drive, one thing to note is where the grub is being installed. I have faced this problem many times. Your OS will het installed properly in the external drive but the GRUB alone will get installed on the internal drive. So, if you boot the external HDD from the same machine, it will work but from another machine it won't work. –  Hashken Mar 21 '14 at 4:46
Now, for the second case. When you use the external HDD as the live USB and try to install the OS in the external drive itself, you need to make sure that the drive is partitioned into two parts, one containing the liveUSB and the other is the partition where you will actually install the OS. Without doing this, you can't use the same external HDD as liveUSB as well as the place to install –  Hashken Mar 21 '14 at 4:46
Thank you very much for the help you have offered thus far. Anyways, I am interested in your first suggestion and, as I am quite a newbie, how can I install the GRUB onto the hdd itself as I want to be able to use this drive as a portable OS. Also, will installing the GRUB on the hdd remove the "missing operating system" error message and go to the GRUB interface for me to pick what to boot on? –  bayf Mar 21 '14 at 4:54

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