If you have nothing to lose, you get to try turning off Secure Boot, turn on EFI legacy or Corporate Stable Mode. All this may have you ask more questions but in short, the PC changed grammatically with EFI so you have more to learn.
Then try GPARTED and if not, then you need a fresh Windows 8 DVD and license to start over.
Bob
Hi - I recently purchased Dell 15r 5521 with windows 8, 500 GB HDD.
On the OS, for C drive it shows 418 GB free of 465 Total Space. Now, I want to reduce the C drive to 50 GB and the remaining 415 GB i want to have it as unallocated space so that I will create partitions out of this 415 GB later.
I tried Shrink Volume wizard on C drive, after that I could get only 225 GB as unallocated space, how do I get the remaining space as unallocated too after giving only 50 GB to C drive.
Please advise.

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