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So for some reason my computer freezes and on restart i get this error (grub loading stage 1.5 grub, loading please wait, error 21) and can't resume to windows. Only way to be able to boot to windows is by a hard reboot.

I never had ubunto on my machine and i have searched google for what so ever information i can find but with no luck...

Edit: im on windows 7 and i tried with a new fresh install without luck.. this has been going for over a year now. but it happens so rarely that i haven't cared for it, but now im finally tired of this s**t.

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GRUB Error 21 Definition: The boot loader fails when installing Ubuntu from Windows operation system

You might encounter Error 21 when you tried to install Ubuntu from Windows or boot Windows after installing Ubunto and the following message appeared:

GRUB loading Stage 1.5 Grub loading, please wait.... Error 21.

This error may occur because you are trying to boot into windows without the external/original drive attached. System optimization might resolve this problem. Try this tool to optimize your system settings and prevents systems conflicts.

Source: — this might be an explanation for your error 21.

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thanks for that information! Think it might be one of the following problems. Software issue - The runtime Error 21 can be caused by a game, software, or a new plug-ins or add-ons that are associated with the program that is generating runtime Error 21, or any runtime Error. Memory related issue - damaged memory sticks, damaged memory blocks, and space allocation issue can cause this error as well. If im not wrong i think it all started when i got my new mobo+cpu+ram. Im going to buy some new ram today or tomorrow. I will report back if it's working or not. – sidiz Jul 26 '12 at 13:21

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