How to add unallocated space to D drive

im15

Distinguished
Nov 26, 2011
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My friend recently showed me a trick on his laptop (We have the same laptop) where he shrunk his C drive, giving him heaps of unallocated space. He then added it to his D drive. However, on mine, extend volume is greyed out for some reason. But first, I would like to add at least half of that space back to C drive because I've just noticed, there's only 318mb free space now. Thank you.

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