Set Active Partition

Typically, your disk always has only active partition. A Windows operating system need to be booted from the active partition, therefore, it is very important. If you have several primary partitions on a disk, you must specify one to be the boot partition. For this, you can set a partition to active, and then this will make that the partition is able to boot an OS. Besides, a disk can have only one active partition.

To set active partition:

 

Note: