"Unknown" space consuming 40GB of SSD?

[xJeST3R]

Just as the title sounds - my SSD has randomly decided to allocate 40GB of space to "Unknown", according to WinDirStar. I don't know what could've caused this, and I've done the obvious things like CCleaner, checked pagefile, did a chkdsk, ran virus scans. I'm just at a loss for words for this and I need some direction.

Thanks for any help.

 

[BringerOfTea]

maybe space sniffer here can offer you a better view?

https://www.howtogeek.com/113012/10-best-free-tools-to-analyze-hard-drive-space-on-your-windows-pc/

 

[Unolocogringo]

A lot of times this is windows system restore and hyperfill.sys. Protected hidden system files.
You can delete all but the last system restore point.
And edit the registry to disable sleep mode if you do not use it.