Windows 10: C drive has 30 gb of unaccounted for storage

My C drive says it has 78.3 GB used but only about 60% of it is accounted for. When I downloaded treesize it said the same thing and was unable to locate where the other 30 gb of storage comes from. What gives?

:)

 

Unaccounted for Dell Laptop Hard Drive space on C: drive SSD

I have a Dell Inspiron 3793 running Windows 10 Home version 1909. The C drive is a 256GB SSD, and I am noticing a bunch of unaccounted for hard drive space (see pictures below). Drive properties show 163GB used, but when I select all the files they only total to 94GB (69GB unaccounted for). If you look on the WinDirStat listing below, there is a 32GB file labelled "<Unknown>". What is going on? What can I do to free up the space?

 

Unaccounted Storage Space

Howdy y'all,

I'm not entirely sure if this has been asked, but I am having an issue that I don't know how to resolve. I am using a 5 year old HP Zbook 15u with 217 GB of storage. As of late my storage has quickly filled up and I only have about 16.1 GB left of free space. Since I need to download AutoDesk Inventor for a project, I need to clear up a lot of space on my hard drive. In order to clear up space I decided to look at deleting some of my applications that I don't use, and move some others to an external hard drive as according to my Storage, 142 GB are being used for Apps & Features. However, when I did a deep dive into how much total space these applications are taking up, I found that they only constitute about 34.1 GB of storage space, not enough to allow me to download Inventor. That leaves roughly 76% unaccounted for, and I have no clue where that space could have gone to. If someone could help me with this problem it would be greatly appreciated.

Bear in mind, I do intend to clear up a lot of space from my Temporary Files, One Drive, Documents, etc., I just want to know where and why I am missing roughly half of my internal hard drive.

I have attached my excel spreadsheet below, and a snippet of my storage.

Storage Space

 

Unaccounted for Dell Laptop Hard Drive space on C: drive SSD

I did the drive properties disk cleanup along with cleaning up system files. Here is TreeSize listing: