When you’re having trouble with your computer’s C drive,  what do you do?

There could be several reasons why your C drive is filling up automatically, such as temporary files, system backups, or large application downloads. One way to free up space on your C drive is to delete any unnecessary files or programs that you no longer use. You can also try using disk cleanup or disk optimization tools to help free up space.

Just transfer unimportant file to a portable storage like external hdd, usb or micro sd, and to boost your pc you need to uninstall apps that takes too much memory, and optimize your drive C, like disk clean up, defragment drive C, delete %temp% or what you called temp files

Increase local disk c partition
Avoid creating big files in desktop , instead store them in other partion which is not system

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