"Shrink Volume" Only Lets Me Shrink by 30GB - But I Have 200GB Free Space?!

sng_x7v

I have a 1TB HDD split into two partitions: C: (500GB) and D: (500GB). C: only has about 300GB of data on it, so roughly 200GB free. I want to shrink C: by about 150GB and add that space to D:.

But when I right-click C: in Disk Management and hit "Shrink Volume," it tells me I can only shrink by 30,720 MB (~30GB). That's it. 200GB free and Windows is saying I can only take 30GB?

I ran diskpart → select volume 2 → shrink querymax and got the same number: 30,720 MB.

What is occupying the other 170GB of supposedly "free" space? I checked with WinDirStat and the used space is genuinely only about 300GB. Where's the rest locked up?

Running Windows 11 24H2. Yes I already tried rebooting.

99bluegz

This is almost always caused by unmovable files sitting near the end of the partition. The Shrink feature can only cut space from the END of a partition, and it can't move files out of the way to make room. If there are system files parked in that area, Shrink will stop at the lowest cluster occupied by an unmovable file.

Common culprits:

Pagefile (pagefile.sys) - often placed in the middle or end of the partition

Hibernation file (hiberfil.sys) - same deal

System Restore points (System Volume Information)

MFT reserved zone - NTFS reserves space at the end of the partition for MFT growth

Try temporarily disabling the pagefile:

System Properties → Advanced → Performance Settings → Advanced → Virtual Memory → Change

Select C:, set to "No paging file"

Click Set, then OK, reboot

Then try Shrink again and see if the available space increases.