When cleaning software cleans up large files, pay attention to what file format it is. Some are useless temporary files that can be cleared, while others are useful, such as large movies, which cannot be cleared.

Pay attention to the file extension. For example, file extensions are mpg, mkv, mp4, mov, flv, etc. This is a video file, usually a movie, and should not be erased. If it is displayed as. Thumbdata- 1967290299-9, it has no extension, and the file name is also a randomly generated number, which is usually a temporary file and can be cleared. Especially if it is in the dcim folder, that is, the temporary file of the album, it must be deleted, because it takes up a lot of space, and often a file will take up several G's.

In addition, if it is a database file, such as vsf.db, be careful. Sometimes it is a useful database. You can open it first, use it for two days, and then delete it if there is no problem. If there is a problem, move it back.