Windows 10 won't update to 1903 from 1803

Try installing the Windows 10 ADK.

I had very similar log errors: regarding Failed to mount WIM file C:$WINDOWS.~BT\Sources\SafeOS\winre.wim

The answer from Jaxrtech on this thread was ultimately what got the update installed for me:

https://answers.microsoft.com/en-us/windows/forum/all/installer-closing-at-6-wimmount0x80070003/b10ba12b-ac29-431d-801a-6163d1620954

I've copied the answer from the linked thread but have modified Step 1 to point to ADK for Windows 10, instead of Windows 8.1

Jaxrtech

At least for me, I was able to find a pretty simple fix for this problem although I was upgrading from Windows 8.1 Update.

AFAIK, this should still fix the problem on Windows 7.

The issue:

It seems that for some strange reason the installer does not include wimmount.sys which is what it's trying to look for. So, it ends up trying to find it at the default location which clearly does not exist causing the installation to fail.

The fix:

So, clearly we need to properly get the installer the recognize wimmount.sys located somewhere. To do that all we need is to get it installed. To do so:

1. Downloadthe "Windows Assessment and Deployment Kit" from:

https://go.microsoft.com/fwlink/?linkid=873065 <-- Windows 10 1803 ADK

https://docs.microsoft.com/en-us/windows-hardware/get-started/adk-install  <-- WIndows 10 ADK other versions 2. Runthe installer (it may take a minute or two for the blue splash screen to go away) 3. "Specify Location"

Leave the default option selected which should be *"Install the Windows..."(FYI: the installer says it uses ~6GB, but we will select only what we need, that being ~50MB, so you aren't killing your internet bandwidth nor wasting time)*Click Next. 4. "Join the Customer Experience Improvement Program (CEIP)"

(You can just leave it set to No unless you feel otherwise :P)

Click Next. 5. "License Agreement"

Click Agree. 6. "Select the features you want to install"

IMPORTANT: Deselect everything except "Deployment Tools"

*(as said, this keeps you from downloading GBs of unnecessary stuff)*Click Install. 7. If you have UAC enabled, click Yes. 8. Wait for the install to complete... 9. Click Close. 10. Try running your Windows 10 install again. The installer should recognize where wimmount.sys and now be able to successfully install Windows 10.

So, let me know how it goes :P

Cheers,

Jaxrtech

Hello,

If you can't install a feature update using Windows Update, you can upgrade to latest Windows 10 version using its ISO file. 

Download the ISO file from here:

https://www.microsoft.com/en-us/software-download/windows10ISO

Then perform the upgrade, using this step-by-step guide:

https://www.kapilarya.com/how-to-upgrade-to-windows-10-using-iso-file

Or you can also perform the clean install with this guide:

https://answers.microsoft.com/en-us/windows/forum/windows_10-windows_install/clean-install-windows-10/1c426bdf-79b1-4d42-be93-17378d93e587

If you still face the issue, try these steps referenced from Genopsyde's post at page 4 of this thread: 

It seems that the installer does not include wimmount.sys and it causes the installation to fail.

1. Download the "Windows Assessment and Deployment Kit" from:

https://go.microsoft.com/fwlink/?linkid=873065 <-- Windows 10 1803 ADK

https://docs.microsoft.com/en-us/windows-hardware/get-started/adk-install  <-- WIndows 10 ADK other versions

2. Run the installer.
3. For "Specify Location"; leave the default option selected which should be "Install the Windows..."

(FYI: the installer says it uses ~6GB, but we will select only what we need, that being ~50MB, so you aren't killing your internet bandwidth nor wasting time). Click Next.

4. For "Join the Customer Experience Improvement Program (CEIP)"; click No. Click Next.
5. For "License Agreement"; Click Agree.
6. For "Select the features you want to install":

IMPORTANT: Deselect everything except "Deployment Tools"

(as said, this keeps you from downloading GBs of unnecessary stuff). Click Install.

7. If you have UAC enabled, click Yes.
8. Wait for the install to complete...
9. Click Close.

Try running your Windows 10 install again. The installer should recognize where wimmount.sys and now be able to successfully install Windows 10.

Hope this helps!

Note: Included link in this reply refers to blog post by a trusted Microsoft MVP.