A user complains that their PC is slow. When you examine, you discover that the free disk space is at 5%. What is the FIRST solution to consider?

If a hard disk is overly loaded and has less than 10% free space, it can significantly slow down. To free up space, the first step is to delete the useless files and uninstall unnecessary apps. Then you should run Disk Cleanup to optimize the HDD. If that doesn't work, you may need to replace the hard drive.