Can't mark OS partition as Active

Pericles

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Greetings,

After formatting my new laptop, I deleted the manufacturer recovery partition, the 100MB partition, resized, merged, created a new Data partition, etc. However, I cannot mark my OS partition (C:) as Active; I can only make my Data (D:) partition Active. Please advise.
 

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My Computer

OS
Windows 7 Home Premium
I'm confused; your screenshot clearly shows partition C: being active.
 

My Computer

Computer type
Laptop
Computer Manufacturer/Model Number
HP ENVY 17-1150eg
OS
Windows 10 Pro x64 EN-GB
CPU
1.6 GHz Intel Core i7-720QM Processor
Memory
6 GB
Graphics Card(s)
ATI Mobility Radeon HD 5850 Graphics
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Beats sound system with integrated subwoofer
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17" laptop display, 22" LED and 32" Full HD TV through HDMI
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1600*900 (1), 1920*1080 (2&3)
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Internal: 2 x 500 GB SATA Hard Disk Drive 7200 rpm
External: 2TB for backups, 3TB USB3 network drive for media
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As Envy runs a bit warm, I have it on a Cooler Master pad
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Logitech Performance Mouse MX
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Hi,

Setting an Active partition is used when you have multiple OS's installed and wish the system to 'Default' to a particular OS when booting up.

I've seen occasions where setting the only OS partition to active can mess up the MBR and a repair is required which resets it back to it's default state to allow booting.

update: It looks as if the 'Active' partition is the first in the string (the string starting from left to right) of partitions from the same disk.


OS
 

My Computer

Computer Manufacturer/Model Number
Compaq Desktop
OS
Windows 7 Ultimate x64
CPU
AMD Sempron Dual Core
Memory
3GB
Graphics Card(s)
NVIDIA GeForce 6150SE nForce 430
Screen Resolution
1024x768
Hard Drives
150GB Sata
Hello Pericles.



There can only be a single active partition per Hard Disk Drive (HDD) as that's the flag that tells WinRE (Windows Recovery Environment) where to repair startup errors or where to create new boot files; do not mark D: as active, it will cause the OS not to boot; have a look at this tutorial at the link below for more info.

Startup Repair - Run 3 Separate Times
 

My Computer

Computer Manufacturer/Model Number
* BFK Customs *
OS
W 7 64-bit Ultimate
CPU
Intel Q9550 Yorkfield
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ASUS P5Q Pro
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8GB Dominator 8500C5D
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ATI : XFX 5870
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Realtek HD Audio 7-1
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1x 47" LCD HDMI & 3x 26" LCD HDMI
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1920x1080P & 1920x1200
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1x 80GB Intel X25-M G2 SSD : 1x 500GB & 1x 640GB WD Caviar Black(s)
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Corsair 620HX
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Cooler Master RC-690
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Tuniq Tower 120, 2x 140mm and 3x 120mm case fans
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Microsoft 500
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Razer Diamondback 3G
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14 Mb/s
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1x Koutech 3Gb/s SATA HDD Hot Swap Rack
Orbital Shark said "Setting an Active partition is used when you have multiple OS's installed and wish the system to 'Default' to a particular OS when booting up"

Having a partition marked "Active" is not just used for dual-boot configurations. Regular, single installations require an active partition too.
 

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Computer Manufacturer/Model Number
Custom-build to order (no brand)
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Windows 7 32-bit
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Intel Q8300 Core 2 Quad (2.50GHz x 4)
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ASRock G31M-VS
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4GB
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Intel G33 Express (Integrated)
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Realtek (Integrated)
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AOC 831W 19-inch LCD
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1366 x 768
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Maxtor 500GB x 1
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Octigen 500W Dual Fan
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Octigen Tower
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2 x case fans
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Generic PS2
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Microsoft Wireless 3000
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2Mbit
Greetings,

After formatting my new laptop, I deleted the manufacturer recovery partition, the 100MB partition, resized, merged, created a new Data partition, etc. However, I cannot mark my OS partition (C:) as Active; I can only make my Data (D:) partition Active. Please advise.
Did you make recovery disks before doing this?
As stated your OS partition is already active. Assuming your OS is ok then the Bare Foot Kid advice is your next step.

Just curious - why did you do this?
 

My Computer

Computer type
PC/Desktop
Computer Manufacturer/Model Number
Own build
OS
Windows 7x64 Home Premium SP1
CPU
Intel i7 2600k
Motherboard
ASUS P8Z68 Deluxe
Memory
G.Skill Ripjaws (DDR3-1600) 2x4GB
Graphics Card(s)
Nvidia GeForce GTS 450; Intel HD Graphics 3000(GT2+)
Monitor(s) Displays
Dell Ultrasharp IPS panel U2311H, Samsung SyncMaster P2350
Screen Resolution
1920x1080
Hard Drives
Samsung 850 Pro SSD 256GB, Samsung SSD 840 120GB, Seagates 1TB Barracuda ST31000528AS x2
PSU
Seasonic M12II 520W
Case
Lian Li Lancool PC-K60
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Case: 1x120mm, 3x140mm CPU: Hyper 212+
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Logitech MK520 (wireless)
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Logitech MK520
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6-7 Mbps
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Norton Security Premium, Malwarebytes on 2 (MSE on 3rd PC)
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FireFox
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Audio: Logitech Z523 2.1
It looks to me as if you deleted your MBR when you deleted the 100MB partition and now you cannot boot. The fix is as Bare Foot Kid says. Marking a partition active without a MBR on that partition will do nothing for you.
 

My Computer

Computer Manufacturer/Model Number
HP, Dell, Gateway, Toshiba - 4 laptops and 2 desktops
OS
Vista, Windows7, Mint Mate, Zorin, Windows 8
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from 1.6GHz Duo to i7
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2x HP w2207
Hard Drives
5x HDD, 7x SSD, 12x Externals
Keyboard
with trackball - no mices
Mouse
Trackball mice
Internet Speed
DSL 6000
In your case follow the tutorial carefully. You will almost certainly need 3 repairs assuming your OS is still in tact.
Your MBR on the first sector of the HDD will need it's partition table updated which includes marking the new active partition entry. (One repair)
Your PBR (partition boot record), boot manager and BCD store used to be part of your 100MB partition. They now need to be in c: requiring the 2 extra repairs.
Hopefully then Windows will load.
 

My Computer

Computer type
PC/Desktop
Computer Manufacturer/Model Number
Own build
OS
Windows 7x64 Home Premium SP1
CPU
Intel i7 2600k
Motherboard
ASUS P8Z68 Deluxe
Memory
G.Skill Ripjaws (DDR3-1600) 2x4GB
Graphics Card(s)
Nvidia GeForce GTS 450; Intel HD Graphics 3000(GT2+)
Monitor(s) Displays
Dell Ultrasharp IPS panel U2311H, Samsung SyncMaster P2350
Screen Resolution
1920x1080
Hard Drives
Samsung 850 Pro SSD 256GB, Samsung SSD 840 120GB, Seagates 1TB Barracuda ST31000528AS x2
PSU
Seasonic M12II 520W
Case
Lian Li Lancool PC-K60
Cooling
Case: 1x120mm, 3x140mm CPU: Hyper 212+
Keyboard
Logitech MK520 (wireless)
Mouse
Logitech MK520
Internet Speed
6-7 Mbps
Antivirus
Norton Security Premium, Malwarebytes on 2 (MSE on 3rd PC)
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FireFox
Other Info
Audio: Logitech Z523 2.1
My computer boots perfectly fine as is. Is there any reason to do all this? I only use a single OS.
 

My Computer

OS
Windows 7 Home Premium
My computer boots perfectly fine as is. Is there any reason to do all this? I only use a single OS.
Now I am confused. In your disk management picture, C is marked as active. And if it boots, what seems to be the problem? We thought you had a boot problem.
 

My Computer

Computer Manufacturer/Model Number
HP, Dell, Gateway, Toshiba - 4 laptops and 2 desktops
OS
Vista, Windows7, Mint Mate, Zorin, Windows 8
CPU
from 1.6GHz Duo to i7
Monitor(s) Displays
2x HP w2207
Hard Drives
5x HDD, 7x SSD, 12x Externals
Keyboard
with trackball - no mices
Mouse
Trackball mice
Internet Speed
DSL 6000
I guess I thought that, because the option to mark it as Active was blanked out, that I couldn't mark it as Active. But according to you all, the reason why it's blanked out is because it's already active. However, perhaps I also made some damage by deleting that other stuff? Would it be easier to just reformat my computer?
 

My Computer

OS
Windows 7 Home Premium
I guess I thought that, because the option to mark it as Active was blanked out, that I couldn't mark it as Active. But according to you all, the reason why it's blanked out is because it's already active. However, perhaps I also made some damage by deleting that other stuff? Would it be easier to just reformat my computer?
No need to reformat. Why go thru the hassle. If it ain't broke, don't fix it.

the reason why it's blanked out is because it's already active
That's funny.
roflmao21.gif
 

My Computer

Computer Manufacturer/Model Number
HP, Dell, Gateway, Toshiba - 4 laptops and 2 desktops
OS
Vista, Windows7, Mint Mate, Zorin, Windows 8
CPU
from 1.6GHz Duo to i7
Monitor(s) Displays
2x HP w2207
Hard Drives
5x HDD, 7x SSD, 12x Externals
Keyboard
with trackball - no mices
Mouse
Trackball mice
Internet Speed
DSL 6000
My computer boots perfectly fine as is. Is there any reason to do all this? I only use a single OS.
Now I am confused. In your disk management picture, C is marked as active. And if it boots, what seems to be the problem? We thought you had a boot problem.
EXACTLY!!:rolleyes:
 

My Computer

Computer type
PC/Desktop
Computer Manufacturer/Model Number
Own build
OS
Windows 7x64 Home Premium SP1
CPU
Intel i7 2600k
Motherboard
ASUS P8Z68 Deluxe
Memory
G.Skill Ripjaws (DDR3-1600) 2x4GB
Graphics Card(s)
Nvidia GeForce GTS 450; Intel HD Graphics 3000(GT2+)
Monitor(s) Displays
Dell Ultrasharp IPS panel U2311H, Samsung SyncMaster P2350
Screen Resolution
1920x1080
Hard Drives
Samsung 850 Pro SSD 256GB, Samsung SSD 840 120GB, Seagates 1TB Barracuda ST31000528AS x2
PSU
Seasonic M12II 520W
Case
Lian Li Lancool PC-K60
Cooling
Case: 1x120mm, 3x140mm CPU: Hyper 212+
Keyboard
Logitech MK520 (wireless)
Mouse
Logitech MK520
Internet Speed
6-7 Mbps
Antivirus
Norton Security Premium, Malwarebytes on 2 (MSE on 3rd PC)
Browser
FireFox
Other Info
Audio: Logitech Z523 2.1
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