If CLEANMGR is run without /sageset or /sagerun, it will start by calculating how much disk space could be saved. This makes the process slower to startup. Although many of these files are often described as "junk" you should carefully evaluate
This tutorial will show you how to open and use Disk Cleanup and extended Disk Cleanup to help free up space by removing unneeded files in Windows 10. Disk Cleanup will only delete Temporary files older than 7 days by default.