When the Windows installer thinks it’s smarter than you…

If you are going to install Windows 7 on a brand new drive, you’ll run into something of a small fight with the installer when you want to partition your drive.
Everything will look as usual… But when you try to create that first partition the installer will throw this in your face:

“To ensure that all Windows features work correctly, Windows might create additional partitions for system files.”

Translated to English this means: “Windows will ALWAYS create a pointless 100megabyte partition that you don’t want.”

If you click Yes, you’ll get your partition, but also a 100MB partition just in front of it. A partition that you didn’t order.

If you click No, you’ll get nothing done at all. Not even the partition you just defined. Basically Microsoft made it impossible to skip this step.

So is the partition really that important?

  1. No, If your drive is already partitioned when you start the Windows installation, Windows will install and the installer will not complain/warn you about a single thing.
  2. No, This partition is used for the windows bootloader, and is only required if you want to use the Bitlocker feature. However, Bitlocker is only available in Windows Enterprise and Ultimate editions. A normal Windows Home installer will still try to create it for some obscure reason.

So, how do we get rid of it?

You can do three things:

  1. Partition the drive on another pc that already has an operating system running.
  2. Follow this intricate series of creations and deletes. Really, this is the easiest, and it only takes a minute. 😉

Lets say you have a 100GB drive and you want to partition it with a two partitions, 30GB and 70GB. (All the size’s here are approximate. Usually they will be rounded off to fit the disk and also be influenced by the fact that a 100GB drive does not actually hold 100GB of data, because of differences between how drivemanufacturers-sales-guys and operating systems measure the amount of space on a harddrive.)

  1. Create the first partition. Enter 30GB as the size.
    Windows will whine, and you’ll click Yes and end up with two partitions:
    One useless 100MB one, and the second, a 29.9GB partition.
  2. Next create a partition using the rest of the drive. This second one will get created just like you ordered.
    So, now you have: 100MB + 29.9GB + 70GB.
  3. Now delete the 100MB partition. The installer will whine again that this partition might be important and bla bla bla.
    You now have 100MB unused space, a 29.9GB partition and a 70GB partition.
  4. Now create your own 100MB partition into the unused space. Since this partition is so small, and there is not enough free space on the drive, the installer will NOT complain this time. The big difference is that this 100MB partition is now YOURs and not a special Windows partition.
  5. Now delete the 29.9GB partition.
  6. Finally extend the 100mb partition up to 30GB

You now have 30GB + 70GB partitions, and you are allowed to select the 30GB one for your windows installation, just like you wanted.

Now send a warm thank you thought to Microsoft for wasting your time 🙂

5 thoughts on “When the Windows installer thinks it’s smarter than you…

  1. Lol, it gave me a good laugh! 🙂

    Indeed this is another annoying invention of Microsoft. Apart from the fact that this partition is useless, it eats up one of the precious max. 4 primary partitions. I ran into problems when installing multiple OS’ses on the disk.
    I’ll definitely try this at next install. Thanks for the idea.
    Will the installer work when I pre-create partitions with Gparted or so, or will the installer whine and quit?

    • The install will work without any problems. This only happens when you create new partitions.

      I find it funny that the installer happily accepts any partitons that are already set up… but if you start from scratch it suddenly has this requirement.

  2. Thank you! Other websites suggested hitting cancel on the prompt but like you said that doesn’t do anything. This worked perfectly 🙂

Comments are closed.