Making a Windows 10 Installation USB Drive Conundrum.

Version Windows 10 v. 22H2

As this is a longish post, I'll start by saying I've made a number of Win10 USB installation drives successfully in the past and present. But I've encountered a few weird failures as well recently, which perhaps someone can explain.

There seem to be 2 main methods of making such an installation drive. (a) Burning a Win10 ISO to the USB, the most popular method, or (b) Extracting/copying the files and folders from the ISO to the USB drive. This is the method I much prefer, as I don't have to use the whole drive unlike method (a). In this case I can divide a 16GB USB drive into 2 or more FAT32 partitions, ensuring that one of them is large enough to be written to for the extraction. The remaining partition(s) can be used for booting, eg a Linux system or just used for storage. In the past my 16GB Toshiba drive could boot to either system when selecting from a UEFI boot menu. I now cleaned the Toshiba USB drive.

So, here's the first problem. When using method (a) I've always used BalenaEtcher, and it's always worked as far as I recall. However, this time it failed either to finish burning successfully, or on the occasion it finished the task I was warned at the start that there was a 'missing partition table', and the resultant USB drive would not boot. And sure enough it didn't. I could make no further progress on repeated attempts with Balena. So I decided to switch to Rufus (first time using), and there was no issue, and my USB drive booted just fine. It seems that this Win10 issue with Balena goes back some years reading their forum, but I've not noticed this until now, and it's never been fixed by the looks of it.

As for method (b), I've always used it successfully for both Win7 and Win10 installation drives. But now it no longer works for Win 10. As I mentioned I use a FAT32 partition. However I noticed one file, install.esd, size 4,160,744,150 bytes or 4.2 GB failed to copy over . So maybe that size file is too big for a FAT32 format. I kept getting an error or failure to complete at that point, using xcopy.

So far everything I had done up to then was from Windows 10. I then switched to Linux, mounted the Win10.iso and and carried out the same copying exercise to the now empty FAT32 partition. To my surprise all of the ISO files copied over, including the large install.esd without a hitch. I then tried rebooting my PC to the UEFI boot menu, and lo and behold my Toshiba USB drive finally appeared, and I was able to boot to it. So any ideas why did this method failed under Windows 10?

dalchina said:

??? DVD (dual layer) ???

May I ask why you've discounted the MS media creation tool?

Thanks.

Does not want the "Overlords" to know that they used that method.

dalchina said:

??? DVD (dual layer) ???

May I ask why you've discounted the MS media creation tool?

Thanks.

I didn't. That's what I used to download the Win10 ISO in the first place. I wasn't intending to use it to make a bootable USB drive. I've done that in the past. I didn't say I couldn't/didn't know how to make a USB drive. That wasn't the point of my post.

FreeBooter said:

In this guide, you will learn the steps to use Rufus to download the ISO file and create a bootable media to install Windows 10 from scratch.

I already mentioned that I used Rufus successfully in my post.

dalchina said:

And thank you for your reply.

Do you not know the tool can create a bootable disk directly?
Create Bootable USB Flash Drive to Install Windows 10

There's absolutely no need to download an iso file and make it difficult.. unless you're, say, creating a multi-boot USB disk.

Yes! I'm well aware of the Media Creation Tool, thank you, but not the point of my post.

Berton said:

The 4GB single-file-size is a limit of FAT32 in Windows which is why I use the MCT to create a bootable USB drive on 8GB, 16GB or 32GB USB Thumb drives. And those drives are only used for that purpose, same for Win11. I get the MCT process started then can go on to doing something else with the drive is being created. 8GB is the minimum requirement as it requires a bit over 4GB free space. Since '94 I've only used the OS process for install the OS, Microsoft for Windows, Linux for Linux, Apple for Macintosh, etc.

I get that, and if you are using just one OS, then that's fine. But for a multiboot choice, as well as the reasons I gave in my OP using method (b) which seems to be a universal method, as well as not wasting space on a USB drive, I prefer that solution.

But neither of my questions have been properly addressed so far. Rather more like 'don't do this, do that instead'. However you did partially answer one of them, in that the FAT32 4GB limit on file size only applies to the Windows system, although having googled I don't see this mentioned specifically to Windows. And I know for a fact that you can transfer files larger than 4GB to a FAT32 partition with Linux, as I did that the other day. But I don't see that mentioned anywhere.