Re: "No operating systems found" on dual boot install
If the Ubuntu installer can't see the partitions correctly, you're asking for major trouble continuing the installation.
Better solution is to go into Win7 Disk Management utility, shrink the Win7 OS to make room for Ubuntu, boot from the Ubuntu CD, and use the "largest free space" option to allow the Ubuntu installer to format the free space correctly.
Ubuntu 12.10; Mint 15; MS Win7 & Win8.
Will not respond to PM requests for support -- use the forums.