Fix the api-ms-win-core-libraryloader-l1-1-1.dll is missing error
You may get the error message api-ms-win-core-libraryloader-l1-1-1.dll is missing when you try to upgrade a PC running Windows 7 to Windows 10.
The error is not limited to the upgrade from Windows 7 to Windows 10 and the Windows10UpgraderApp.exe. Windows 7 users ran into the error when they tried to run other programs on Windows 7 as well, but the bulk of issues is caused by Microsoft's upgrade tool.
The error is thrown after you run the Windows 10 Update Assistant on the Windows 7 machine. The Update Assistant downloads the Windows 10 installation files fine but throws the error when it starts the installation of the operating system.
The Error Message
The error message reads:
The program can't start because api-ms-win-core-libraryloader-l1-1-1.dll is missing from your computer. Try reinstalling the program to fix this problem.
The description is not that useful. It does highlight that a dll library file is missing on the computer, but gives no indication where users may get it or which program they may need to re-install to add it.
How to fix it
The fix is simple thankfully. All you need to do is copy a DLL file from the system32 folder of the Windows 7 installation to the root Windows10Upgrade folder.
- Open c:\windows\system32\ using Explorer or another file manager.
- Type "wimg" quickly to jump to the right file. Or, browse until you find the file wimgapi.dll this way.
- Select wimgapi.dll, right-click on it, and select copy from the context menu.
- Open c:\Windows10Update\
- Right-click on the folder and select Paste.
- Confirm that you want to replace the pasted DLL file with the existing one.
- The process may require elevation. Accept the prompt as well.
Restart the upgrade to Windows 10 once you have copied the file wimgapi.dll from the system32 folder to the Windows10Upgrade folder.
The download step is skipped this time as the files are still cached on the local system. You should notice that the installation proceeds as planned at this point. Congratulations, you fixed the error.
Closing Words
The error api-ms-win-core-libraryloader-l1-1-1.dll is missing appears to be a packaging error that Windows 7 users ran into after the release of the Fall Creators Update.
The file api-ms-win-core-libraryloader-l1-1-1.dll that the Windows 10 Upgrade Assistant uses is not a Windows 7 DLL file and is therefore not on machines running Windows 7.
What makes this particularly difficult to troubleshoot is that you cannot get the missing dll file for Windows 7.
Microsoft needs to release an update for the Windows 10 Upgrade App to fix the issue. Users and admins who run into it in the meantime can resolve it with a quick copy and paste action.
i cant find windows10uprgade or pdate anywhere and my computer is windows 8 but its not bloody working
thanks
Thank you very much bro, keep it up
Thank You !!
Thanks sir… Started the installation..
How do you fix the problem on Win 7 and I didn’t run the 10update
Your awesome thank you for sharing this information.
now it just keeps failing
Thanks so much for this! I heard that the fix involved messing around with System32 files and was immediately terrified, but your step-by-step process made it quick and easy.
Great advice,works well
Thanks
Wow, wild fix for this. THANK YOU
Thank you… so freaking much.
Thanks:) A very simple solution.
All was good but when i put c:\Windows10Update\ it says it cant find it?
C:\Windows10Upgrade it may be on some pc’s
Thank you! I thought upgrading from Windows 7 to Windows 10 would be a nightmare for this evening. This post helped me to correct the error that Windows upgrade was throwing at me.
Thank You
i ran into this problem on new years eve trying to get my other Laptop from Windows 7 to Windows 10. i found the fix on another site. But i can verify that this will fix the problem.
Hey how do I eat horrible nutrition so that I have stents and heart attacks, what’s the best beer to drink and fastest cigarretes to lung cancer and liver failure diabeties and heart failure.
I was just wondering maybe I could get the BEST advice to my timely end.
Seriously I want to upgrade my computers too, I mean they need to be FAST instead of having all those decades of pesky family photos or old recorded songs of dead people who worked for years..
Of course it’s my fault for not educating myself on the proper replacement of failed backup systems and failed recovery and allowance of younger friends to format C every month so that no data really ever exists of your (and I mean “OUR” this time) existance anyway.
This is for the best, I mean why would you possibly want to remember the HORROR or back stabbing or even attempt to unwind the madness I am ranting on about. It’s a good thing I don’t drink. But it’s a good thing you care even less about your History, or Past or Family. I must upgrade the wallet to bitcoin and computer to a flash disk, website /network in the cloud and ISP/wireless. NOthing wrong with tracking, just look at the stop sign, it needed 4 cameras.
You need to switch to decaf.
WTF?
Are you alright?
all went well up to the final step of windows 10 upgrade, it locked at 99% in the installing windows phase. i left it like this overnight. I did check the Task Manager and it said the upgrade is running….12 hours at 99% and no change….
Good Fix, thanks for sharing.