1. Clean it up with third-party software such as CCleaner first.

2. Change the path of user files, my documents, my music, my videos, my desktop, etc. To a non-system partition (files will also be moved).

3. Reduce the space occupied by system restore of system disk, set most virtual memory as non-system partition, and clean up the system restore point.

4. If you don't use the hibernation function, you can enter cmd in the start menu, right-click to run as an administrator, and enter powercfg-off in the newly opened black window to turn off the hibernation function and delete the hibernation file.

5. Delete irrelevant programs, especially those installed on the system disk. You can also use the method of moving. For example, to move the media player attached to the system to the Program Files directory on drive D, first move the Windows Media Player folder under C:\Program Files\ to D:\Program Files\, and then open cmd as an administrator. Just enter mklink/j "c: \ program files \ Windows Media Player" and "d: \ program files \ Windows Media Player", and it will be moved to drive D. The Windows Media Player icon in the start menu can still be used normally. It's easy to recover, just delete the shortcut of Windows Media Player under C:\Program Files\ and move the one on D disk.

6. Enabling disk compression in the Program Files folder property can reduce the space occupation and will not affect the system performance {nttwqz original answer}.

7.% windir% \ software distribution \ download contains automatically updated files, which can be deleted after updating.

8. If Office 20 10 is installed, you can also delete the MSOCache folder of drive C.. Changing office functions after deletion requires an installation disk.

9. Clean up the cache or temporary files of commonly used players and change the path to other partitions.

10. Change the download software path to another partition, and the file will also be moved.

1 1. It is recommended to reinstall the operating system at least once a year. This is the most effective way to clean up garbage and fix mistakes!

12. Now no one can tell you what you cleaned up or what caused it, because we don't know which software you installed, and it is impossible to use all of it. Most cleaning software, methods and batches can only clean up those recognized garbage, and the effect is very limited. Here is a solution-use search to find files added on the same day and files with relatively large volume, use resource monitor (running perfmon /res) to monitor the process of writing a large number of files to disk, and determine which software is cheating according to file names, attributes, directories, etc. , combined with your installed software, system logs, search engines, etc. , and then you can determine the problem, and then it will be easy. I believe you know how to do it ...