I'm still not sure how you are getting the result you are getting at the beginning and ending of your drives. But I will continue to monitor the thread to learn what is actually happening and how it is fixed.
As I showed in my screenshots on post #24 of this thread, somehow I too had a small 11MB unallocated area at the right end of my DISK3 (as shown by PW).
I don't' how it got there, other than somehow over the years and drive upgrades as has been mentioned. Sometimes a source partition from one drive may have been copied directly to a second drive, sometimes partitions on one drive were resized, sometimes partitions were copied out from source location to an intermediate USB 3.0 backup drive and then copied back when the drive hardware upgrade/replacement was complete. And depending on whether the 3rd-party product offered an option to resize the receiving partition to make it different than the size of the sending partition, this may or may not have also occurred. I only use Partition Wizard and Macrium Reflect, so those are the only two products which could possibly have explained my 11MB of unallocated space. I NEVER USE DISKMGMT.MSC, so it couldn't possibly have been something that Windows did.
Probably all of these possible explanations are reasonable. Certainly I've never seen unallocated space of any kind just spontaneously appear once the partitioning has taken place, however it took place. I can't possibly imagine having multiple partitions on a drive with zero unallocated space at left or right (as viewed from a particular 3rd-party product), and then a day or two later suddenly open space now exists! Seems impossible, unless there was something else that took place which could somehow resize the existing partitions... and for sure you'd know about it, since you were the one who did it. Otherwise, partitions don't just resize themselves, and it seems highly unlikely that PW can present a view of the partitions on a drive one day that is different from that same view two days later, if nothing had taken place in between to cause the partition boundaries to be adjusted.
Anyway, as was shown in my post #24, I simply used PW to "extend" the adjacent partition to the left of the 11MB unallocated space, pushing the slider all the way to the right so that all of the available unallocated space would be absorbed by the partition to its left, and zero unallocated space would remain. That happened, and it's "still holding". Still no unallocated space has returned.
I would recommend that PW be the tool used to do just that if necessary, no matter how the unallocated space came to exist. Just "extend" the partition to the left (or right) of this unallocated space to consume all of the adjacent unallocated space, and that should be the end of it. I trust PW.
