Re: Successful Dual Boot with Lenovo Y500
First of all, do NOT use Gparted to shrink the Win8 OS partition. Doing so risks corrupting the filesystem and rendering Win8 unbootable. Use the Win8 Disk Management tool to do the shrinkage. And, when done, reboot into Win8 a couple of times to let it do filesystem adjustments. Wubi doesn't create partitions, so if you want to use Wubi, then you won't have to mess around with partitioning at all.
Second thing to do, after that, is to download and install the free version of Macrium Reflect. Once that is installed, image off the Win8 OS to an external drive or USB stick. NOW, you have a backup that you can restore if anything goes terribly wrong with Win8.
Third, use the Win8 option to create a Repair disk. I don't know if it will also work with USB, but if it does, you should choose that option. This allows you to repair any Win8 boot loader problems without having to boot into Win8.
Ubuntu 15.04 Mate, Mint 17.1; MS Win 8.1, Win10 TP.
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