I want to repartition my 2T hard drive to shrink the C drive from 1T to .5T so I can make the other partition where I keep my data 1.5T. The C drive will still be more than half empty. I understand that, after optimizing the C drive, I can shrink it around the operating system without loss of functionality. My question is can I add the freed up .5T to the other partition without loss of that data or will I have to reformat that whole partition? I already back up the data to an external drive but want to know if there's a way to do this without having to go through the many many hours it'll take to restore 900G of data files.