This problem was weird and I had never encountered such a problem before. Actually I wanted to shrink the size of my system drive (C drive) because I had moved all my documents including C:Users to D drive so that if something happens to the Operating System, my data remains safe all the time.
When I opened C drive properties by right clicking the C drive and going to Properties, I saw that the space used was more than what I was expecting. So I decided to dig deeper and enabled the view of all system files and hidden files in C drive, selected all files and opened their properties. This was showing different size from the drive properties. I ran Disk Cleanup but it was of no use as it didn’t suggest much space could be recovered. Something else was wrong. I decided to use a third party tool to see where my space was going visually. For this, I selected WinDirStat which is a wonderful tool for visualizing the spaced occupied by files and folders in any drive or folder. The best thing about WinDirStat is that it also comes as a portable tool so I can run it without installing. The first run of WinDirStat was not useful and it showed the same amount of space used as by selecting all files in C drive. Then I found some folders which were showing zero byte size. This was unusual as System Volume Information and C:UsersPublic were also zero bytes. The common thing in these folders was that I was unable to open these folders.
I closed WinDirStat and ran it with administrative privileges. WinDirStat started showing the correct stats after running with administrative mode. The culprit was an VHD file which was taking about 30 GB of space and Windows Explorer was showing it as zero bytes due to incorrect permission settings.
I had to set the folder permissions to become the owner myself and then deleted the file to save extra space. I hope this will be helpful for those who think Windows Explorer is not showing the correct disk space usage. It is usually due to permissions on folders to which we don’t have access and WinDirStat was helpful in sorting out the problem. By the way, I am using MiniTools Partition Wizard free edition to resize my drives. I have been using it for quite a long time and only once it has corrupted my drive structure and data. So you should always back up your data before doing anything sensitive.
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