Creating a Bootable Drive

Are you doing a clean install or just updating your PC ?

Janothin said:

It would be used to do a clean install across multiple workstations.

I'd suggest using the MCT/Media Creation Tool to create a bootable USB Thumb drive of sufficient capacity, minimum 8GB for either x86 or x64. If wanting to use the choice of having both x86 and x64 version use a 16GB drive. It will be formatted/reformatted as FAT32 and bootable with most computers. Using seemingly over-capacity drives takes into account the loss of space due to partitioning and formatting, i.e. a 4GB drive will not hold 4GB of data. The same applies to CD or DVD discs, formatting always takes a bit of space.

Here is a manual (non-Rufus) procedure originally posted by @NavyLCDR that I recorded and saved (with slight modifications). I've used it many times now and it works under all boot conditions, UEFI/GPT/MBR or BIOS/MBR.

1. Download and save the ISO you need to your hard drive.
2. Insert the USB flash drive.
3. Open a Administrator Command Prompt and enter: diskpart (if it isn't an administrator command prompt, it will ask for administrator permission).
4. list disk
5. select disk # <- replace # with the actual disk number of the USB flash drive
6. clean <- this will erase the disk selected above, make sure you selected the USB flash drive!
6a. If the flash drive shows as GPT then you need to convert it to MBR: convert mbr
7. create part pri
7a. sel part 1
8. format fs=fat32 quick
8a. assign
9. active
10. exit
11. exit - and if the first Command Prompt was not an Administrator Command Prompt, exit that one too.
11. Mount the saved ISO file. If you are using Windows 8 or 10, you only have to right click on it and click on mount. If you are using Windows 7, then you must use a program like WinCDEmu to mount the ISO file:
WinCDEmu - the easiest way to mount an ISO. And more...
12. Copy all the files and folders from the mounted ISO file to the USB flash drive.

I just downloaded the latest WIn 10 ISO via MCT.

install.esd is less than 4GB:



So the procedure I posted should work okay. I don't know if it will fit on a 4GB flash drive or not.
The ISO is 3.86GB (4,147,445,760 bytes).

Edit: I just went through the process after downloading the latest Win 10 via MCT. Worked fine and compleated with no problems. Would not work with an install.wim. Would exceed the 4GB maimum size for a file with FAT32.

With Rufus there is a chance of screwing up and getting a flash drive that you will not be able to install from. It's happend often which is why @NavyLCDR posted the manual instructions I then posted (with modifications) above. This will work with UEFI/GPT/CSM or BIOS/MBR.