What is the 100mb partition Windows 7 SOMETMES creates on install?


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  • 9 months later...

if i want to install win7-64bit on a pc now, should i create the partitions myself or let win7 do it and have the 100mb boot partition. Would there be any issues if dual booting with linux for example, or drive imaging software?

^ouch, is that because of dual booting?

Naa its because I was an idiot and tried to install OSX along side Windows - which worked.. but then I wanted rid of it, deleted the partition and tried to repair the windows MBR which failed so had to reinstall Windows 7 on the OSX partition and install EasyBCD to get back into this partition

Its a right mess, later today I am going to delete the 2nd windows partiton, make a new partition as big as free space I have left - copy all my stuff to there, and format - its doing my head in lol

The 100mb is Windows 7 repair partition. Press F8 before Windows boots and you will see a "Repair Your Computer" option. It comes in handy when Windows cannot boot.

Yes, it is also uses for BitLocker, but that's its secondary purpose.

The 100mb is Windows 7 repair partition. Press F8 before Windows boots and you will see a "Repair Your Computer" option. It comes in handy when Windows cannot boot.

Yes, it is also uses for BitLocker, but that's its secondary purpose.

Did you read the thread? The partition does not contain any repair stuff. You can confirm this yourself by simply mounting it. The repair environment is located on the boot volume of the OS it belongs to and is bigger than 100MB (this makes sense if you think about it, since the recovery feature is specific to a single OS, and not the entire system.) The partition is used only to host the boot loader. It is the system volume. The only purpose it serves in current versions of Windows is to enable full volume encryption and to separate the system volume from the boot volumes. In versions before Vista it was common that the system and boot volume was the same, which added complications for systems with multiple OSes installed. You couldn't reformat the volume that was set as both system and boot without also losing the ability to boot from all other boot volumes you had. Having the system volume be a separate dedicated partition makes this easier. It also makes it slightly more difficult to accidentally delete the boot loader. It wasn't that uncommon for novices to delete the "random" files in the root of the disk to "clean it up" and thus end up with an unbootable system.

If none of this is an issue for you, there is absolutely no reason to create the partition if you don't want to. You can manually create the partitions you want in the installer instead, and doing so has no negative consequences.

Did you read the thread? The partition does not contain any repair stuff. You can confirm this yourself by simply mounting it. The repair environment is located on the boot volume of the OS it belongs to and is bigger than 100MB (this makes sense if you think about it, since the recovery feature is specific to a single OS, and not the entire system.) The partition is used only to host the boot loader. It is the system volume. The only purpose it serves in current versions of Windows is to enable full volume encryption and to separate the system volume from the boot volumes. In versions before Vista it was common that the system and boot volume was the same, which added complications for systems with multiple OSes installed. You couldn't reformat the volume that was set as both system and boot without also losing the ability to boot from all other boot volumes you had. Having the system volume be a separate dedicated partition makes this easier. It also makes it slightly more difficult to accidentally delete the boot loader. It wasn't that uncommon for novices to delete the "random" files in the root of the disk to "clean it up" and thus end up with an unbootable system.

If none of this is an issue for you, there is absolutely no reason to create the partition if you don't want to. You can manually create the partitions you want in the installer instead, and doing so has no negative consequences.

The 100 MB system partition is used primarily as BitLocker partition for BitLocker encryption. Additionally, it also holds the Windows Recovery Environment (WinRE) and boot files with boot manager for booting up the computer for troubleshooting when there is no Windows 7 installation DVD disc on hand.

If you don't believe me, try deleting the partition.

The 100 MB system partition is used primarily as BitLocker partition for BitLocker encryption. Additionally, it also holds the Windows Recovery Environment (WinRE) and boot files with boot manager for booting up the computer for troubleshooting when there is no Windows 7 installation DVD disc on hand.

No, it does not. I explained this. The recovery environment is OS-specific. You can't have a single one for all installed OSes. For this reason, it's located in the \Recovery folder on the individual boot volumes (a boot volume is a volume that contains OS files, a system volume is a volume that contains the boot loader). You can confirm this yourself by looking at this folder. You can also confirm that the recovery environment is larger than 100MB by looking at this folder. You can also confirm that it's not located on the 100MB partition by simply mounting it and looking on it. It's a standard NTFS partition. There is no need to wonder or speculate here, you can easily confirm it all yourself.

If you don't believe me, try deleting the partition.

I never create it on my systems in the first place.

  • 4 weeks later...

Its for bitlocker

Actually, it's only created if a partition is the first (or only) primary partition *and* it is greater than 175 GB (the smallest drive or partition I've seen with that dreaded 100 MB unlettered System Restore partition is my 200 GB SATA-150 DiamondMax). My current 500 GB WD Caviar Green WD500AVVS has the same size System Restore partition (it's still unlettered; therefore, it only shows in Disk Management).

In both cases, Windows was installed clean (onto a hard drive without partitions).

Considering that the same 500 GB WD can now officially be considered *paltry* for a desktop drive, 100 MB is chimp-change (no, that is NOT a mis-spelling).

It is the system partition (the proper name for the partition that contains the boot loader), not system restore partition. There's nothing related to system restore or repair on it, just the boot loader. After all these pages, I can't believe this still isn't clear.

It is the system partition (the proper name for the partition that contains the boot loader), not system restore partition. There's nothing related to system restore or repair on it, just the boot loader. After all these pages, I can't believe this still isn't clear.

Err, yes it is a somewhat system repair partition. If you create a managed install with the WAIK (like a lot of OEMs do) you can use that partition to house your OS recovery files, etc. By default it has a few system files and also the boot files, etc, but you CAN use it to repair your computer if you set it up that way.

Err, yes it is a somewhat system repair partition. If you create a managed install with the WAIK (like a lot of OEMs do) you can use that partition to house your OS recovery files, etc. By default it has a few system files and also the boot files, etc, but you CAN use it to repair your computer if you set it up that way.

It's a 100MB partition, so no, you can't fit all these things on it. It should also have been obvious that we are talking about what Windows uses it for by default, since it is the one creating it. You could also mount it and store your porn on it if you wanted, but that doesn't mean porn storage is its purpose. I can't believe it's such a "mystery." It's a standard NTFS partition and you can freely check what's on it.

It's a 100MB partition, so no, you can't fit all these things on it. It should also have been obvious that we are talking about what Windows uses it for by default, since it is the one creating it. You could also mount it and store your porn on it if you wanted, but that doesn't mean porn storage is its purpose. I can't believe it's such a "mystery." It's a standard NTFS partition and you can freely check what's on it.

Yes, the default contents of that drive are basically the boot manager & system volume info, as well as a few more random files (plus bitlocker if you are using it).

But you are totally wrong in the fact that you can't put a recovery image on there. With WAIK you can put whatever you want, and create the partition as big as you want. This is what OEMs are now using for Win7, and we have done the same at my workplace (usually a 5GB partition with a custom image.wim with our default image/software).

But you are totally wrong in the fact that you can't put a recovery image on there. With WAIK you can put whatever you want, and create the partition as big as you want. This is what OEMs are now using for Win7, and we have done the same at my workplace (usually a 5GB partition with a custom image.wim with our default image/software).

You can also create 52 other partitions as well of various sizes, and fill them with various random things if you want. One for each week of the year. What this thread is about is the one hundred megabytes (100 MB) large partition that Windows creates by itself to host the boot loader, nothing else.

The 100MB partition is created for the Windows 7 Bitlocker feature.

Info

"As a result, Windows 7 automatically creates the necessary disk partitions during installation to greatly simplify BitLocker deployments."

I think it's only created by Ultimate and Business, and only when you install on a bare unpartitioned drive.

Incorrect, I have it on Professional x64 (Windows 7).

It I do believe contains boot files and system files, which should be left alone and not deleted ever.

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