BleachBit - When your computer is getting full, BleachBit quickly frees disk space.
Glary Utilities - The No. 1 Free, Powerful and All-in-one utility for cleaning your PC
CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
System Mechanic - System Mechanic uses patented technology to help fix PC errors and restore speed. The software is compatible with multiple versions of Microsoft Windows.
Ultimate Windows Tweaker - Ultimate Windows Tweaker is a freeware Tweak UI Utility for tweaking and optimizing Windows.
Advanced SystemCare - Free optimization software & registry cleaner for Windows 10, 8, 7, Vista and XP. Advanced SystemCare Free to speed up PC, clean registry and repair system in one click.