I want to shrink the OS partition on my internal drive. I'm getting tired of my Acronis backups taking two hours to complete. The size of the drive is 1TB, formatted NTFS. The first partition on the C Drive is labeled OEM (39MB) and I have no idea what it contains. The second partition is labeled Recovery(11.96GB) (System, Active, Primary). The third partition is labeled OS (794.23GB)(Boot, Page File, Crash Dump, Primary). The fourth and final partition is my Acronis Secure Zone (125.29GB) (Primary). I don't back up either of my external drives, as both of them contain the same information so that if one of them takes a crap on me I have an exact duplicate on the other one.
I would like to reduce the OS partition to 150GB, allowing 50GB for the Shadow Copies. All my Windows Backups (full backup only, overwritten) go to one of my external drives. All my Acronis backups (full backup only, overwritten) go to each of the external drives and the Acronis Secure Zone. All my files (pictures, videos, music and copies of downloaded software) are stored on the external drives.
I attempted to shrink the OS partition (794.23GB). Once the drive was analyzed it showed:
Total size in shrink in MB: 813,292
Size of available shrink space in MB: 128,196
Total size after shrink in MB: 685,096
I don't understand why I cannot substantially shrink the OS volume beyond 128,196MB. I don't understand what type of immovable file(s) would prevent me from doing so but then again, I can't understand how to shave without cutting my face. I have defragged the OS partition using PerfectDisk 11 Professional, using defrag only (not SmartPlacement) and consolidated free space using the same application prior to attempting to shrink the OS partition and I'm still offered no more than a 128,196MB shrink.
Also, I've read somewhere that it could be advantageous to move the page file to a partition other than the OS partition. If that's true, I have no idea how to do it.
Thank you in advance for your time and any assistance provided and please excuse my ignorance.
I have provided two screen shots.