How do I upgrade from 10.04 or 11.10 to 12.04?
Already run Ubuntu V10 but won't automatically upgrade.
Can I just install V12 'over the top' or do I have to save all files and settings etc to disc first?
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go to this link and it will show you the steps.
once you have updated it once keep doing it until you reach ubuntu 12. you have to do this because all the other has bug fixes and other secuirty patches.
this method is good if you want to keep all your data and you wont lose anything and you will still have your software you wont lose anything.