Since i have had laptops for the past year with SSD drives(faster but smaller), i have spent more time monitoring storage space on my C drive.
Disk cleanup is a very useful tool. With many “major” windows 10 updates, that’s the way you can clear up the “previous windows installations” option.
During one of my recent cleanups, i noticed two new options. I wanted to bring these to your attention as one is ok to enable, if needed, but one i absolutely would NOT touch.
If you are in serious need of space, this could be an option. However all it does is compress certain files. Yes that frees up some space, but depending on the file(s) performance could be affected as the file will need to be uncompressed before opened. I wouldn’t recommend this option unless as a last resort.
Under NO circumstances would i endorse you deleting all of your system restore points. These are “checkpoints” saved before your computer at critical times (before software installs, etc.). They allow you to roll back your computer to an earlier date if you are encountering issues. If you are in dire need of space, and you have many system restore points, there are other ways to free up this space specifically then this option.
As always, please feel free to ask any questions you might have.