Windows – When is it safe to remove installation media during Windows 10 upgrade

Unfortunately Microsoft has pulled the 1511 update for the media creation tool, and I need that update so that the old Windows Professional key will be recognized and I don't have to perform an upgrade first before doing a clean install.

Microsoft only temporarily pulled the updated Media Creation Tool. If you really want to use the 1511 Media Creation Tool it still exists on the Microsoft servers here

You can still find the 1511 version of the media creation tool on various sites, I tried that but I only get the choice between the "Windows 10" and "Windows 10 N" editions. With the non-1511 tool directly from Microsoft I got also the choice for Windows Professional there.

You want to choose Windows 10. The 1511 Media Creation Tool would download a universal x86 x64 Windows 10 Home/Windows 10 Professional .ISO.

Are the installation media for Windows 10 Home and Professional actually different? Or can I install Windows Professional with a USB drive created with the "Windows 10" edition selected in the media creation tool?

The build 10240 Windows 10 Home and Windows 10 Professional .ISO files are indeed different. This is no longer the case with the 1511 .ISO. The updated .ISO file is a universal Home/Professional x64/x86 .ISO file.

I had the same weird behavior when trying a Windows 10 upgrade. Ultimately, my decision was to install from scratch. Definitely the right call. My main issue was that I didn't have a partition structure that Windows liked. STRONGLY recommend a fresh install on a physical drive (SSD of course) with only the Windows partitions: System, MSR, Windows, and Recovery. Yes, 4 partitions on Drive 0. I was able to use the guidance from MSDN about UEFI/GPT-based hard drive partitions.

I didn't have to use Windows PE as specified in the article because you can run the CreatePartitions batch from any Windows machine. Using the GPT version (not the MBR version) is highly advisable for 2TB and high drives (I had a 256G SSD, several 3TB drives, and a 5TB drive). Just save this to a CMD file and CHANGE THE DRIVE NUMBER to your physical drive. Run DISKPART LIST DISK to verify the disk number.

rem    Create four partitions for a UEFI/GPT-based Windows PC.
rem    Adjust the partition sizes to fill the drive as necessary.

select disk <NUMBER>
clean
convert gpt

rem == 1. System partition =========================
create partition efi size=100
format quick fs=fat32 label="System"
assign letter="S"

rem == 2. Microsoft Reserved (MSR) partition =======
create partition msr size=16

rem == 3. Windows partition ========================
rem ==    a. Create the Windows partition ==========
create partition primary 
rem ==    b. Create space for the recovery tools ===
shrink minimum=500
rem ==    c. Prepare the Windows partition ========= 
format quick fs=ntfs label="Windows"
assign letter="W"

rem === 4. Recovery tools partition ================
create partition primary
format quick fs=ntfs label="Recovery tools"
assign letter="R"
set id="de94bba4-06d1-4d40-a16a-bfd50179d6ac"
gpt attributes=0x8000000000000001
list volume
exit

The first time I did it, I ran all of the commands manually from CMD. Much easier to see what's going on that way. Also, if you have Windows "Disk Management" (run diskmgmt.msc) running, you'll see the results in near real time.

Hope this helps. It saved me, and my Windows install has never been happier.

Pro tip: don't enter your serial number when installing... make sure you have a good install and just enter it later. Click "I don't have a product key" instead.