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I just installed Ubuntu 12.04 from a bootable USB (created in Ubuntu itself). Everything was fine with installation, but after installation, I need to plugin the USB to start-up.

Ubuntu does not read from the USB (just a tiny activity at startup), but without the USB attached, Ubuntu will not be started. Black screen frozen by _ sign.

I think something for independent start-up has not been correctly copied

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Is it possible that you installed the bootmanager on your USB stick? – Mordoc Apr 26 '12 at 19:16
I doubt if there's something wrong with that. I just followed the instruction given at to create my bootable USB. Clean formatted USB. – All Apr 26 '12 at 19:25
up vote 1 down vote accepted

I would reinstall grub. Would certainly appear that grub is installed to the USB. But with the information available it's hard to tell

Assuming you want the bootloader to the MBR, boot into your Ubuntu. Remove the USB and then open a terminal.


sudo grub-install /dev/sda

to install grub to the mbr, update grub

sudo update-grub

Reboot without the usb.

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The problem did not happen when creating the USB stick, but during the installation. It seems that the installer installed the bootmanager on your USB stick instead of putting it on your hard disk.

I am now performing a test installation on my laptop and I noticed that when I select custom installation, the installer will select by default to install the bootmanager on the USB stick, so maybe it's doing it also when selecting the other types of installation.

Which kind of installation did you choose?

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