Add Space to Windows 10 OS Partition from the Adjacent Volume Upgrade the System Drive with a New Larger Oneġ. Move Unallocated Space to Windows 10 OS Partition via Diskpart.exe Extend Windows 10 OS Partition with a Third-Party Tool If this way doesn't work well on your Windows 10 computer, it's time to expand the Windows 10 OS partition with the following 4 ways. When the Windows 10 OS partition is almost full, it's recommended to free up the OS partition firstly. Normally, the larger the available space of the Windows OS partition, the faster the computer runs. Windows 10 OS (operating system) partition is usually the C partition in a computer. 4 Ways to Expand Windows 10 OS Partition-Tested and Workedĭoes your Windows 10 computer run slower and slower because of the insufficient Windows OS partition space? What can you do at this time to speed up your Windows 10 pc?