Installing Windows, ANY VERSION has removed linux and its boot manager.
This is a well worn area of discussion. But to narrow down which old discussion to read, we use the distro's name.
Here's one to start with -> https://help.ubuntu.com/community/RecoveringUbuntuAfterInstallingWindows
Bob
On my Dell XPS M1330 (4gb ram, 2.2ghz processor), I had a nice installation of Vista and Ubuntu 10.04. I upgraded to Windows 7, the transformation went great and all of my files went over to the windows 7. Now, when I boot I no longer choose which partition to boot on, it just loads Win7. I've read around a little and it seems windows 7 tries to take over as the only os on the computer. How to I get the option to choose a partition on startup? or did windows 7 eliminate my ubuntu 10.04 during the upgrade?

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