Diskpart question-convert from GPT to MBR on a flash drive

AddRAM said:

Not 1 good reason comes to mind.

4 partitions on a system 250/256 GB ssd is just ridiculous, but I don't want to get into that.

Especially since Windows now needs a recovery partition. it's hidden, no use to you in normal operation, but it still counts against the four primary partition limit.

sportsfan148 said:

Thanks very much Navy. You definitely cant be any clearer than that The Diskpart method is the way forward for me now having always used the Media Creation Tool or Rufus method in the past. Hopefully Microsoft wont let the Windows 10 ISO get over 4gb because then there will be a problem with the Diskpart method with FAT32 not working with files over 4gb. I know its getting closer nowadays. I believe the Windows 10 ISO was around 3.5 GB the last time I checked

The issue is not size of iso, but size of install.wim/esd which cannot exceed 4GB on a fat32 drive.


Actually, it is easy to create bootable flash drives with any size install.wim/esd.

You basically create two partitions on flash drive - first is fat32, second is NTFS. Copy all files in iso except install.wim/esd to fat32 folder. Copy everything to ntfs folder.

Then it boots from fat32 but finds install.wim/esd from ntfs.

People who create custom install.wim greater than 4GB use this method, or other ways which split the install.wim.

MS will certainly be able to develop the MCT if the install.wim or install.esd ever exceeds 4GB. The 1803 install.esd is around 2.5 GB iirc, so it will be a long time before this will be an issue anyway.

NavyLCDR said:

The recovery partition is not needed by Windows and it can easily be deleted.

Tried a clean install of 1803 yet? I tested that for the first time yesterday on a legacy mbr system, starting with an empty disk, cleaned with diskpart.

Just the two partitions, System Reserved and the C: drive. No recovery partition, instead reagent /info said it was using the C:\Recovery folder.