How to Remove the 100MB Windows 7 System Reserved Partition

[Jonathan_King]

How to Remove the 100MB Windows 7 System Reserved Partition

WARNING: This involves deleting the boot partition, then repairing. Failure to follow these instructions exactly may leave your computer in a non-bootable state.

NOTE:

• Make sure the C drive is a Primary partition before you begin. Type diskmgmt.msc into the start menu to access the above window.
• You must have a Windows 7 Installation or Repair disc to do this. If you do not have a DVD, you can create a Repair Disc.

EXAMPLE: 100 MB System Reserved Partition

Here's How:

1. Boot from your installation or 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 [Windows disk number].

5. Enter list partition, followed by select partition [100MB partition number].

6. Enter delete partition override.

7. Enter select partition [Windows partition from step 5], then enter active.

8. Close the command prompt.

We have deleted the partition, and Windows will be unable to boot at this point. Now it is time to write a new boot loader and BCD to the Windows partition.
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9. Follow the instructions in Brink's tutorial for running a startup repair.

 

[cboucher]

There is an easier way to get rid of the 100MB boot partition. Before you install Windows 7, use a partition manager such as Parted Magic to create the primary partition and format it as NTFS. Then, when you run the Windows 7 installer, select the preformatted partition. That way, Windows doesn't ever get the chance to partition your hard drive.

 

[Jonathan_King]

That's true; you can also do it from Diskpart before the installation. However, often people don't realize that until afterwards, and want to remove it. Give them what they ask for, I guess.

 

[cboucher]

However, often people don't realize that until afterwards, and want to remove it. Give them what they ask for, I guess.

Huh, they really must not be paying attention because the installation program warns you that it's going to create that extra partition before you click OK to start the installation process...

 

[Jonathan_King]

By the time you get to the installer, it's too late to do anything about it. Even it they are warned, there is no way to avoid it, except by using Diskpart or a third-party partitioning program.

Not that the 100MB partition hurts anything; there's nothing wrong with just leaving it there, unless you need that extra Primary partition for some reason. I guess it was easier just to write a tutorial once and for all, rather than talking everyone out of it.

Come to think of it, not having the 100MB partition does make boot issues easier. Having that there means one more level of complication, often times.

 

[cboucher]

We make dual boot lab machines quite often where I work and that 100MB partition causes problems when ghosting and reimaging. I find it much easier and faster to get rid of it before it ever gets created. Kinda like when the Terminator went back in time to kill John Conner's mother.

 

[Jonathan_King]

LOL.

I did the same to mine; I couldn't stand seeing that extra partition in Device Manager!

 

[cboucher]

The stupid thing is that it doesn't even use the whole 100MB. I think there was something like 80MB free space last time I saw one of those.

 

[Jonathan_King]

I'm wondering if it stores other data at times as well. I've heard rumors of Bitlocker keys being stored there, etc. I had no way of testing it at the time I put together that guide (still don't!), but I've heard zero complaints, so I'm willing to bet it's safe.

But, what is 100MB in these days of 500-2000 GB hard drives?

 

[cboucher]

But, what is 100MB in these days of 500-2000 GB hard drives?

Enough to store AC/DC's Highway to Hell album...