This browser is no longer supported.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(128, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EA%3C/text%3E%3C/svg%3E)
I'm currently on windows 7 and whenever I run Windows 10 upgrade assistant it gets to 99 then tells me I'm missing api-ms-win-core-libraryloader-l1-1-1.dll. I've tried running it on a clean boot, I've ran system cleanups to repair any corrupt files, I tried removing my antivirus, and still it won't work.
Does anyone have any other methods to fix so I can upgrade? any help appreciated!
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
I was one of the first to have the problem. Been researching it and found the solution late last night...much simpler than that posted.
I'm running the upgrade right now. When you get the error do the copy/paste and hit Retry.
Copy and Paste wimgapi.dll from C: Windows/System32/wimgapi.dll to C:Windows10Upgrade/wimgapi.dll
The date on the System32 dll is 7/13/17.
Good Luck
So you all have the exact instructions I used, here is a copy.
I had the same "api-ms-win-core-libraryloader-l1-1-1.dll" missing issue when upgrading Windows 7 to Windows 10 and finally I saw your post and tried fixing the problem by "Replacing C:\Windows10Upgrade\wimgapi.dll with the one from C:\Windows\System32\wimgapi.dll". It works. The Windows 10 upgrade is in progress.
Yes same issue here.. Fresh Dell Load of Windows7 passes all checks then crashes with same error as you.
missing api-ms-win-core-libraryloader-l1-1-1.dll
Same exact problem, does anyone have a solution?
