Step 1: Open Run dialog box by simultaneously pressing Windows and R keys. If you don’t have the required amount of unallocated space next to system partition in the partition table, follow the easy instructions provided in Method 2 to successfully extend your system drive. If you don’t have some unallocated space next to the system drive, Windows will not show extend volume option even if you have enough free space on another partition. While it’s possible to extend the system partition using Windows Disk Management tool, there must be some unallocated space right next to the system partition.
Method 1 Extending system partition using Windows Disk Management Tool