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I'll paint the original situation: Windows won't boot. Trying to replace it with Ubuntu so my laptop will work.

Now I have two USB sticks. One is about 1 GB, and the other is 8 GB, recently purchased for the purpose of installing Ubuntu.

I followed the directions laid out by the help files, and used the Universal USB Installer to install Ubuntu onto both USB sticks. Oddly enough though, the 8 GB stick will not boot even the trial of Ubuntu on the laptop. Meanwhile the 1 GB could (that is, until something happened and I had to format it and it's now only 556 MB). So to run the trial and unsuccessfully attempt to install it, I had to have both USBs plugged in at the same time. Before it wouldn't let me install it, giving me various errors about partitions and /dev/sda. But now it won't even boot up at all.

I've gone to the BIOS screen and made it so it always tries to boot from the USB stick and still nothing happens. The 8 GB has Ubuntu correctly installed onto it and it still refuses to boot up even a trial, let alone allow me to try to install. I just get a black screen.

What is going on here? I'm not a computer expert so it would help if you can simplify any answers you can give. Thanks.

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You said there were error messages. What exactly did they say? Without this, it may be very hard for anyone to answer you may need to try installing again to see what they are. Also, what is the result of checking the MD5 sum on the ISO image and checking the integrity of the write? (That says "CD" or "disc" but it applies equally to USB media.) – Eliah Kagan Jan 31 '13 at 16:45


  1. You have a hardware problem like a failed hard disk drive. If this is why Windows isn't booting, of course that will translate to any other OS. The dev/sda errors make me suspect this. Depending on the make/model of your machine there may be hardware tests you can run from BIOS or boot selection screen.

  2. The install media has gotten messed up. Sounds like you've done some pretty intense formatting and playing around with those sticks. I'd open up a program like UNETbootin and make sure it can recognize the formatting on those sticks and see them as writable.

  3. Last but not least it could be an issue with booting from usb, or a problem with the usb port itself. You could rule these out by burning a disc if you are able to.

Hope that helps.

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