Common operations on free up space are format partition, delete volume, move data from one partition to another. Those operations might be help in data partitions sometimes, but not always good far system partition; because you don’t know which document is system requirement. Sometimes data partition is not able to delete or format in order to keep data, for example, photo partition is the last partition you want to delete for free space. Some you need one partition manager to do the entire disk related job without data loss.
Related Reading: Low disk Space on C Drive
Partition Extender will do the extension job without loss data, the theory is to extend partition size with unallocated space or free space that can be shirk from other data partitions, so your data with stay safe in the whole operation progress.
For example: C (nearly full) + D (full sized) + E (a lot of free space)
In this situation, it's not likely to extend C Drive with D partition size, because D Drive is also full of capacity. It's a solution to make free space from E partition. Disk management here can do the shrink job.
That's all you can do within Disk Management, maybe you will say the next step is to extend volume in C partition, but, the result is that Extend Volume right now is grayed out, you cannot click on it, because the unallocated space is not in the right spot to extend.
OK, then you can run out Partition Extender, you can see the space you just shrank from E partition is now shows as unallocated space.
In the first interface, the disk map is already reloaded
And then Partition Extender will finish the job in seconds if the size you extended is not much. Besides, steps above says Click on rightwards-arrow actually comes out same result of dragging handle to the end, because D partition is full too, there's no more space to shrink, Partition Extender will just take unallocated space to extend.