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- What Happens When I Upgrade Ubuntu? 3 answers
I'm running 12.04 and want to upgrade to the latest stable version. How do I do that without losing my data files?
If I'm correct, there is no way to upgrade from 12.04 to 13.10 directly unless you reinstall Ubuntu completely, which will lead to a loss of data.
My advice is, backup your important files - this is important. Whether or not your files are supposed to be deleted does not matter - accidents can and will happen.
After backing up, you can upgrade from 12.04 to 12.10, then to 13.04, then to 13.10 by running
in a terminal.
However, this is extremely slow as you will be upgrading 3 times. My recommendation is, copy your files to another device (perhaps using the 13.10 Live CD) and reinstall your Ubuntu.
Summary: Two choices.