When the hard drive is full, your computer may run slowly, and you can't store new files or data. Many users have confronted hard drive full for no reason or C drive full for no reason issue on Windows 10. Full stepsĬlean up junk files, delete temporary files, increase C drive space, and upgrade to a larger HDD/SSD. When there are a lot of hidden files or folders on your hard drive, you will find hard drive full but no files. If your hard disk has errors with a corrupted file system, you will see the hard drive full without reason. Recycle Bin is part of the hard drive and keeps all the temporary deleted files. You should suspect a virus or some malicious software you unknowingly installed.