So far the best solution for Windows 10 disk 100% percent usage

1. In windows 10 search bar, enter cmd, in search result right click "command prompt",select "Run as administrator".

2. In DOS command window, type: chkdsk /r c: (or whichever disk you installed Windows 10),it will ask that it can lock the drive right now,
would you like to do disk check next reboot? answer Y

3.Reboot, it will check and repair specified disk. it usually is stuck at a percentage but still working, just be patient and wait.
C drive is 90 G on my laptop, it takes about 30 minutes, my desktop C drive 130G, it takes one hour.
somebody online even said it takes a day or days, not sure how huge is their disk.

4. It might be better to combine with other solutions like http://hometownwind.blogspot.ca/2017/06/windows-10-too-slow-disk-usage-100.html and disable all unused services.

5.Disable unnecessary services: In windows 10 search bar, enter services, in search result right click Services, select "Run as administrator".
right click a service > properties, change "Startup type" to manual or disabled, then Apply, OK.


Following are some services which can be safely set to MANUAL/DISABLED:

Connected User Experiences and Telemetry
Diagnostic Policy Service
Diagnostic Tracking Service
Distributed Link Tracking Client (If your computer is not connected to any network)
dmwappushsvc
Downloaded Maps Manager (If you don't use Maps app)
IP Helper (If you don't use IPv6 connection)
Program Compatibility Assistant Service
Print Spooler (If you don't have a printer)
Remote Registry (You can set it to DISABLED for Security purposes)
Secondary Logon
TCP/IP NetBIOS Helper (If you are not in a workgroup network)
Touch Keyboard and Handwriting Panel Service (If you don't want to use touch keyboard and handwriting features)
Windows Defender Service (If you don't use Windows Defender program)
Windows Error Reporting Service
Windows Image Acquisition (WIA) (If you don't have a scanner)
Windows Search (If you don't use Windows Search feature frequently)
Apart from the above mentioned services, You can also set a few other services startup type to MANUAL such as services installed by your graphics card driver (Intel, nVidia, AMD, etc),
your sound card driver (Realtek, Creative, etc).