Why this Warning triangle on my C drive icon?

ow Disk Space: The most common reason for a warning triangle is that your C drive is running low on disk space. Check your available storage and consider deleting unnecessary files or running a disk cleanup.

File System Errors: There may be issues with the file system on the drive. You can run the built-in Windows utility called Check Disk (chkdsk) to scan and repair file system errors:

Open Command Prompt as an administrator.
Type chkdsk C: /f and press Enter. This will schedule a disk check the next time the system restarts.