Partition - Mark as Active

How to Mark a Partition as Active in Windows 7​

Contents

• Mark as Active in Disk Management
• Mark as Active in Command Prompt
• Mark as Active in Partition Wizard

   Information

Marking a partition as active on a basic disk means that the computer will use the loader (an operating system tool) on that partition to start the operating system.


At various times the need to mark a partition as active arises. This will show you two ways of doing so.

   Note

• You must be logged on as an administrator to mark a partition as active.
• You can't make a logical drive or an extended partition active. Only a primary partition can be made active.
• There can be only one active partition per physical hard disk.
• If you have multiple hard disks installed on your computer, it's possible for each hard disk to have a partition set as active. However, the active partition on the first hard disk that your computer's BIOS detects is the one that will start the computer.

   Warning

Do not mark a partition as active if it doesn't contain the loader for an operating system. Doing so will make your computer unbootable.

If you disable the Disk Defragmenter service, then you will get the error below when you try to do anything in Disk Management. If you get this error, then make sure that the Disk Defragmenter service is set to only Manual.

METHOD ONE

Mark as Active in Disk Management

1. Type diskmgmt.msc into the start menu, and press enter.

2. Right click on the partition you want to mark as active, and select Mark Partition as Active.


That's it!

If you can't boot into Windows, use method 2.

METHOD TWO

Mark as Active in Command Prompt

1. Boot into your Windows 7 installation or repair disc.

   Tip

If you don't have a Windows 7 installation DVD, you can Create a Repair Disc.

2. When you get to the language screen, press Shift+F10.


3. Enter diskpart, then list disk after diskpart is loaded.


4. Enter select disk [number of the disk the partition is on].


5. Enter list partition, followed by select partition [partition number].


6. Type active.
There you go! You can now close the command prompt and reboot your computer.

   Tip

You can also use this method from within Windows. Type cmd into the start menu and press enter.

METHOD THREE

Mark as Active in Partition Wizard

1. Download a copy of the Partition Wizard Bootable CD.

2. Boot it up, right-click on the partition, and select Modify>Set Active.

Related Tutorials

---

• How to Mark a Partition as Inactive in Windows 7 and Vista
• Data Partition
• How to Delete a Partition or Volume in Windows 7
• How to Extend a Partition or Volume in Windows 7
• How to Create a New Partition or Volume in Windows 7
• How to Shrink a Partition or Volume in Windows 7

 

[gregrocker]

We use this tutorial many times every day to rescue Win7.

 

[NewTo7]

Thanks, unfortunately it did not work in my case and in fact MiniTools Partition Wizard is what caused the boot problem in the first place, an installed copy never succeeded in a reboot to copy the partition. FWIW a Paragon rescue disk saw the partition as invalid, although GParted identified it as NTFS.

 

[mjf]

Thanks, unfortunately it did not work in my case and in fact MiniTools Partition Wizard is what caused the boot problem in the first place, an installed copy never succeeded in a reboot to copy the partition. FWIW a Paragon rescue disk saw the partition as invalid, although GParted identified it as NTFS.

Doesn't really explain enough of the background to your problem.
I've found the miniTools (installed) version fine for smaller jobs eg. setting partitions active etc. But for anything substantial, particularly partition moves, you should use the Bootable version, with the Windows OS out of the way. Apart from much greater flexibility, the bootable PW has proven more accurate at times in reporting accurate partition information compared with Windows Disk Management.

 

[NewTo7]

Thanks, unfortunately it did not work in my case and in fact MiniTools Partition Wizard is what caused the boot problem in the first place, an installed copy never succeeded in a reboot to copy the partition. FWIW a Paragon rescue disk saw the partition as invalid, although GParted identified it as NTFS.

Doesn't really explain enough of the background to your problem.
I've found the miniTools (installed) version fine for smaller jobs eg. setting partitions active etc. But for anything substantial, particularly partition moves, you should use the Bootable version, with the Windows OS out of the way. Apart from much greater flexibility, the bootable PW has proven more accurate at times in reporting accurate partition information compared with Windows Disk Management.

Well my particular problem is OT to this thread anyway, and there is always more info whether relevant or not.

What you said applies to everything anyway, and yet I've used an installed copy of similar programs if not PW itself to copy partition fine for XP. What I don't understand is why a simple reboot for partition copy has created a situation where the straight forward boot fixes of different utilities will not work.

 

[Shadowjk]

My friend has Ubuntu on a seperate Harddrive and wants to uninstall but doesn't have the Internet or a Startup repair Disk so He was wondering that if he marks his Windows Drive as Active will it get rid of the GRUB Bootloader?

Josh

 

[mjf]

Thanks, unfortunately it did not work in my case and in fact MiniTools Partition Wizard is what caused the boot problem in the first place, an installed copy never succeeded in a reboot to copy the partition. FWIW a Paragon rescue disk saw the partition as invalid, although GParted identified it as NTFS.

Doesn't really explain enough of the background to your problem.
I've found the miniTools (installed) version fine for smaller jobs eg. setting partitions active etc. But for anything substantial, particularly partition moves, you should use the Bootable version, with the Windows OS out of the way. Apart from much greater flexibility, the bootable PW has proven more accurate at times in reporting accurate partition information compared with Windows Disk Management.

What you said applies to everything anyway, and yet I've used an installed copy of similar programs if not PW itself to copy partition fine for XP.

My comments apply to everything
If you don't want to take the advice re bootable PW don't take it.

If other installed programs work then use them.

This is a Windows 7 forum not an XP forum.

 

[Jonathan_King]

Hi Josh,

I'm not sure where the GRUB is installed to. If it's on the same hard drive Ubuntu is installed on, you should be able to just disconnect the drive, mark the Windows partition as active (if it's not already so), and run a startup repair. It's possible a startup repair will be unnecessary, give it a try!

If simply marking the partition as active doesn't do the trick, a repair disc can easily be created. See both methods in this guide: http://www.sevenforums.com/tutorials/2083-system-repair-disc-create.html

 

[oxymoron02]

Method not working.

Having severe difficulties getting any of the above (and other related) methods to work. A quick run-down of my partitions:

Hitachi is partitioned in two; C: houses Win7 and D: houses my old installation of WinXP.
WinXP is listed as System,Active (and Primary Partition); while Win7 is listed as Boot (and Logical).



When I come to try step one I immediately hit a hurdle; I have absolutely no option to set the partition as active. It's not greyed out, it simply doesn't even exist in the right-click context menu.


When I run diskpart and navigate down to the Hitachi, I am met with this.



Partition 1 is Windows XP
Partition 0 is Windows 7
Partition 2 is .... Wait- What? Three partitions?

Trying to set 0 as active nets me the message "Virtual Disk Service error: The specified partition is not a primary or logical volume." Ok. Balls.

Trying to set 2 as active brings further calamity: "The specified partition type is not valid for this operation." Well screw you then, computer.



The startup repair method was similarly unsuccessful, presumably because I had yet to flick the active status over to the Windows 7 partition.


I would love to say that I realise I'm doing something wrong, but being as I can't even perform step one I would hesitate to assume such. Perhaps someone on here can highlight what is causing my computer to be a complete hassle.

Thanks,
- Oxy

 

[Jonathan_King]

Hello Oxy,

Using Partition Wizard, right-click on your C partition, and select Modify > Set Partition as Primary. You should then be able to mark it as Active. While you have Partition Wizard up and running, you might find it fastest just to use that.

Good luck, post back any questions you may have!

 

[oxymoron02]

Unfortunately this doesn't work for me. I get the good ol' greyed out problem here.



Brief question because I don't have time to do it now (I'm already late for work! )
If I were to set the partition to primary and reboot (that's the part I don't have time for), would it then allow me to make the partition active once Windows restarted?

 

[Jonathan_King]

Yes, you should be able to mark the partition as Active after you set it to primary. The one thing I am unclear on is whether or not you'll be able to do that to the main boot drive from Windows. Someone who does more of this kind of work than I do should be able to tell you, but all I can say is if it doesn't let you, boot into the recovery console and run the Diskpart commands.

 

[oxymoron02]

I have now successfully rendered the Win7 partition as primary and the WinXP partition as Inactive. However, it still won't let me set the Win7 partition to Active, and I'm a little wary of rebooting to see if it will allow this as I have a feeling the machine will become unbootable once Windows shuts down.

It's so typical of my machine, of all the computers in the world, to throw up this kind of problem where so many others have managed to perform the exact same operation without flaw.

 

[chev65]

Doesn't Windows 7 require the 100MB system reserved partition in order to become the System, Active Primary Partition? I don't see it there in the disk management for C drive.

 

[oxymoron02]

Isn't it that partition called 'System Reserved'?

I also have some astonishing news. After screwing up my boot manager (I became impatient and attempted two steps in one boot), I actually succeeded in rendering Win7 as primary and active, and WinXP as logical and inactive, -all using pwhe-, then used the startup recovery three times technique which repaired the boot files to the Win7 partition. I've now wiped XP (goodbye, old friend...) and am in the midst of merging partitions using pwhe.

Currently sitting twiddling thumbs on my Android tablet waiting for the next thing to go wrong. And oh look, the Google+ app keeps crashing.

 

[chev65]

Isn't it that partition called 'System Reserved'?

I also have some astonishing news. After screwing up my boot manager (I became impatient and attempted two steps in one boot), I actually succeeded in rendering Win7 as primary and active, and WinXP as logical and inactive, -all using pwhe-, then used the startup recovery three times technique which repaired the boot files to the Win7 partition. I've now wiped XP (goodbye, old friend...) and am in the midst of merging partitions using pwhe.

Currently sitting twiddling thumbs on my Android tablet waiting for the next thing to go wrong. And oh look, the Google+ app keeps crashing.

Yes it says system reserved and it also says Active, where the actual C drive doesn't say Active and only says Primary Partition. Can you tell if pwhe- added the system reserved partition?

I'm wondering why Windows wouldn't let you do that, hmmm.

As you found out, you can usually fix the boot manager, you can also fix it using the command prompt. bootrec /fixboot and bootrec /fixmbr.

http://www.sevenforums.com/tutorials/104341-bootmgr-missing-fix.html

Saying goodbye to XP was a welcome sight for me but that was years ago.

 

[oxymoron02]

True enough your actual Win partition should be System Active, as far as I understand it, but I'd cut my losses while I was ahead and just be thankful it's working

I'm genuinely sorry to have gotten rid of XP but I was hanging on to it out of sentimentality . That and because my friend won't make the leap' so when we want to lan it up on Sins of a Solar Empire I had to boot into XP. Well no more!

 

[herbun]

"Do not mark a partition as active if it doesn't contain the loader for an operating system. Doing so will make your computer unbootable."

How do I know where the boot loader is located at?

Thanks

 

[Jonathan_King]

Hello herbun,

I'm sure there are other ways, but open Disk Management ("diskmgmt.msc" into the start menu), and look for the partition labled "System". That's your target.

BTW - the warning up there is valid in most cases, yet there may be times where it is necessary to mark a non-System partition as Active, namely when you're about to create a new boot loader on another partition. Use with care.

 

[herbun]

Thanks for your reply. I got a little problem though, there is no partition labeled as "System".

It's in german, however, another german version (win 7 prof) has also a partition called system.

Maybe its the second partition on "Datenträger 0", I can't see whats written there, but it *should* be the same as the status in the table above(as it is on the other german pc), and there I don't find "System" either. See attached image.

Edit:The 7 version I am talking about is home premium btw.