That will happen when there are unmovable files. There are a few tricks you can do to unlock some of these files, or you can use an external utility that you re

That will happen when there are unmovable files. There are a few tricks you can do to unlock some of these files, or you can use an external utility that you reboot into. This article is from a vendor of such a utility, but it also describes how to unlock some of the unmovable files within Windows: https://www.disk-partition.com/articles/shrink-volume-with-unmovable-files-4348.html https://www.disk-partition.com/articles/shrink-volume-with-u...