How to Set Partition as Active or Inactive

Active partition is computer boot partition. And the startup files of operating system are installed in this partition. Partition C: in Windows systems is usually set as active partition by default while active partition in Linux is set according to specific setting. When the system is booted, operating system on active partition will perform drive image in order to assign drive letters to primary partitions and logical partitions. All primary partitions will be imaged first while logical drives are assigned according to subsequent letters.

Let’s see how to assign drive letter manually.

1.The Definition of Hard Disk Active Partition

Active partition is computer boot partition. And the startup files of operating system are installed in this partition. Partition C: in Windows systems is usually set as active partition by default while active partition in Linux is set according to specific setting. When the system is booted, operating system on active partition will perform drive image in order to assign drive letters to primary partitions and logical partitions. All primary partitions will be imaged first while logical drives are assigned according to subsequent letters.

Tip: Generally, there is only one active partition in a hard disk, and the rest partitions are all inactive. Read our guide Active vs Inactive Partition to know more.

2.The Methods for Setting Partition as Active or Inactive

The system partition must be the active primary partition for booting. And it must lie in the hard disk accessed by computer when OS is booting. There should be only one active system partition in one disk. Several basic disks are allowed to exist on computer, each of which has its own active partition. However, you can start computer only by one specified disk. If you want to use another OS, you must set the system partition of the certain OS as active before restarting computer.

You can't mark an existing dynamic volume as active, but, you can convert basic disk which includes active partition to dynamic disk. This active partition will become active simple volume after disk conversion. If active partition is not the current system partition or boot partition, it will become simple volume and its record in partition table will be lost. Then, it will become inactive.

Actually, active partition is the primary partition with boot data. It can achieve taking over starting tasks and other operations from BIOS in order to boot system.

You had better have only one primary partition, or it may be difficult for you to manage your disk. You can generally divide a 10G primary partition in a small hard disk. For a big one, you can divide a primary partition which is about 15G to 20G. You don't need to divide a primary partition that is too large.

Set Partition as Active (only 32-bit)

Hard disk active partition 1

The first method: you can use Windows interface.
1.Enter “compmgmt.msc” in “Run” (to open Computer Management).

2.Click “Disk Management” under “Storage” of “Computer Management”.

3.Right click the partition which needs setting active and click “Mark Partition as Active”.

The second method: you can use command line
1.Enter “cmd” in “Run”.

2.Enter “diskpart

3.Enter “list disk”.

4.Enter “select disk 0”, for example, we want to set the first partition of disk 0 active.

5.Enter “list partition”.

6.Enter “select partition 1”.

7.Enter “active”.

Set Partition as Inactive
You can only use command line to set partition as inactive, because the “Mark Partition as Inactive” option in Windows interface can't be chosen now.
1.Enter “CMD” and run diskpart by inputting “DISKPART>”.

2.Enter “LIST DISK” to determine ## number of your hard disk.

3.Enter “Select DISK 0” to set your disk as current operating hard disk.

4.Enter “LIST PARTITION” to determine ## number of your disk partition.

5.Enter “Select PARTITION 1” to set the first partition as current operating partition.

Enter “INACTIVE” to set the current partition as inactive.