The Message: You cannot shrink a volume beyond the point where any unmovable files are located. The message is showing in the shrink volume window.
Enter the amount of space to shrink in MB: You need to enter less than its default number. Sometimes even you entered a smaller number, however it won't start shrinking since the unmovable files dominates the sectors that prevents the shrinking. It usually happens on the C drive when shrinking volume.
Causes: Unmovable files block the shrinking volume that Windows cannot shrink volume
Easier Faster and Free Fix: Shrink a volume using a free tool Partition Resizer which offers more flexiblities when Windows cannot shrink a volume beyond the point due to unmovable files or other limits
Video1: Shrink C extend D or E
For Windows 11/10/8/7 => Download Partition Resizer Free [100% Free]
For Windows Server 2025-2003 => Download Partition Resizer Server [Free Demo]
Also read: how to shrink C extend another drive
Video2: How to shrink D extend C drive without losing data
Also read: How to shrink one volume to extend another
Here is a comparison table that shows the limits of shrinking a volume between Partition Resizer and Disk Management or Diskpart, the CMD provided by Windows too.