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I installed Ubuntu 12.04 LTS into Windows XP using Wubi.exe. Update Manager tells me an upgrade to 14.04 is available, and the Manager has an "Upgrade" button. If I click that, will it upgrade my wubi-installed Ubuntu in Windows and leave Windows intact, or will it install the upgrade on top of Windows, thereby, eliminating Windows? I want to keep things just as they are except have Ubuntu 14.04 LTS instead of 12.04 LTS. Would it be better for me to uninstall 12.04 and do a fresh install using Wubi.exe (14.04)?