P: Lightroom launch mfc140u.dll missing file on Windows

Error message, mfc140u.dll file not found when launching, tried reinstalling with no sucess

Correct answer Sameer K

Welcome to the Lightroom Community. I'll help you figure this out. The mfc140u.dll is part of Microsoft Visual Studio.

Please try these steps & let me know how it goes.

In the Creative Cloud app, press CTRL + ALT + T (Win) to launch Creative Cloud Troubleshooter & select 'Close Creative Cloud and related processes' > click on Go.
Go to 'Add or Remove programs' in Windows search & find all the installations of Microsoft Visual C++ Redistributable (all years).
Uninstall them completely. Even if there is an option to repair them, please uninstall all the existing MSVC++ packages.
Download a fresh package of installers for MSVC++ from this link: Microsoft Learn: Latest Support VC Redist.
Right-click the downloaded file and select Extract All.
Reinstall all packages (32bit & 64bit) & then restart the computer.

Let me know how it goes from here. Thanks!

Sameer K

Participant

the app will not open. says the code execution cannot proceed because mfc140u.dll was not found

Community Expert

You are using Lightroom or Lightroom Classic, but have posted in the Photoshop forum.

If you are using Lightroom (cloud based), post here:
https://community.adobe.com/lightroom-ecosystem-cloud-based-677

If you are using Lightroom Classic, post here:
https://community.adobe.com/lightroom-classic-672

Participant

Community Expert

The mfc140u.dll is part of Microsoft Visual Studio. Can I suggest that reinstalling the Visual C packages would restore mfc140u.dll for you.

In the Creative Cloud app, press CTRL + ALT + T (Win) to launch Creative Cloud Troubleshooter & select 'Close Creative Cloud and related processes' > click on Go.
Go to 'Add or Remove programs' in Windows, search & find all the installations of Microsoft Visual C++ Redistributable (all years).
Uninstall them completely. Even if there is an option to repair them, Uninstall all the existing MSVC++ packages.
Download a fresh package of Latest Supported installers for MSVC++ from this link: .
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist
Right-click the downloaded file and select Extract All.
Reinstall all packages (32bit & 64bit) & then restart the computer.

Regards. My System: Windows-11, Lightroom-Classic 15.3, Photoshop 27.5, ACR 18.3, Lightroom 9.3, Lr-iOS 10.4.0, Bridge 16.0.3 .