click here to see how to set active partition using command line
Launch the Macrorit Partition Expert, you'll see all detail information of the partition and disk.
Select a primary partition which you want to active, and then click Set Active Partition.
Click OK to add the pending Set Active operation.
In the end, Click the "Commit" button, the changes can take effect.
NOTE: Setting this partition as active partition will set other primary partition(s) inactive.