Windows 10 System Partition Requirement UEFI - NTFS or FAT32

I was reading about Bitlocker and noticed this:

Because pre-startup authentication and system integrity verification must take place on a partition other than the encrypted operating system drive, BitLocker requires that your computer has at least two partitions:

• An operating system partition (usually drive C) that is formatted with NTFS.
• A system partition that is at least 350MB. This is where Windows stores files needed to load Windows at boot. The system partition must not be encrypted and should also be formatted with NTFS for computers that use BIOS firmware and with FAT32 for computers that use UEFI-based firmware. This drive is often hidden in Windows Explorer. You can configure one or more partitions for your data (drive D, E, etc.) and enable BitLocker on them.

Securing Windows 10 with BitLocker Drive Encryption Microsoft MVP Award Program Blog

On my UEFI PC's (on which Windows 10 was installed in UEFI mode), Windows created a 450MB NTFS recovery partition and a 99MB FAT32 no name partition. Which one of these are they talking about above, and does this mean that I cannot enable bitlocker because there is not a 350MB+ FAT32 partition?

spunk said:

You have a 450MB Recovery Partition, and a FAT32 File system partition, so you are good to go.

Is that a typo in the article then? It strongly implies that you need a 350MB+ FAT32 partition for bitlocker on UEFI systems.

Oubadah said:

Is that a typo in the article then? It strongly implies that you need a 350MB+ FAT32 partition for bitlocker on UEFI systems.

You need to expand your FAT32 EFI System Partition to at least 350mb in size. I would recommend using MiniTool Partition Wizard to do it:
Best Free Partition Manager for Windows | MiniTool Partition Free

If you have the standard UEFI layout, you will have to take the space from the front of your C: drive partition (250 MB). There will be a small MSR partition that does not show up in disk management, you will have to move that over to the right, up against the new starting location of the C: drive partition. Then expand the EFI System Partition. Make sure to click the apply button. MiniTool will restart the computer to shrink the C: drive partition. The operation occurring when the computer reboots will look scary, but don't worry about it, it will do what it is supposed to do.

NavyLCDR said:

You need to expand your FAT32 EFI System Partition to at least 350mb in size. I would recommend using MiniTool Partition Wizard to do it:
Best Free Partition Manager for Windows | MiniTool Partition Free

If you have the standard UEFI layout, you will have to take the space from the front of your C: drive partition (250 MB). There will be a small MSR partition that does not show up in disk management, you will have to move that over to the right, up against the new starting location of the C: drive partition. Then expand the EFI System Partition. Make sure to click the apply button. MiniTool will restart the computer to shrink the C: drive partition. The operation occurring when the computer reboots will look scary, but don't worry about it, it will do what it is supposed to do.

Why doesn't the Windows 10 installer do that in the first place?

Oubadah said:

Why doesn't the Windows 10 installer do that in the first place?

I don't know, I don't work for Microsoft.

Oubadah said:

Why doesn't the Windows 10 installer do that in the first place?

Mine was done at the install of Win10, new OEM computer from ASUS with a new clean Toshiba HDD. Upgrades from Win7 w/SP1 or Win8.1 may be a different story.

Berton said:

Mine was done at the install of Win10, new OEM computer from ASUS with a new clean Toshiba HDD. Upgrades from Win7 w/SP1 or Win8.1 may be a different story.

Mine are clean installs from the windows 10 AU ISO. It's always: 450MB NTFS (recovery) -> 99MB FAT32 (system) ->16MB (MSR) -> C:\.

Apparently the recovery partition is wrong too, because if you perform an AU upgrade on a pre-AU installation (which used the same partition structure above), it will generate a new 800MB+ recovery partition at the end of the drive (and the end of the drive is where it's supposed to be according to this article: UEFI/GPT-based hard drive partitions).

So the Windows installer:
- Makes an undersized system partition, too small to allow one of it's key features to work.
- Puts the recovery partition in the wrong position.
- Makes the recovery partition too small so that it has to be re-made during build updates.

Great

I think that article I referred to in the OP is wrong. I'm having a hard time finding other sources that say Bitlocker needs a 350MB system partition. This page, dated 5/4/2016, says 100MB minimum. https://msdn.microsoft.com/en-us/windows/hardware/commercialize/manufacture/desktop/bitlocker-drive-encryption