We have used computers many years, and we encountered low disk space problem many times, I think it’s time to upgrade to a new and big hard disk to solve the problem and enjoy better performance. There are many solutions. Copy the whole disk to a bigger one, or only transfer operating system to another drive. The former way spends lots of time, if we choose the latter way, we can migrate OS to SSD, which speed is faster than HDD, and the move process spends less of time. What’s more, without re-installing the operating system.