unable to open adobe lightroom

Question

while trying to open adobe lightroom app, i am getting error message of mfcdll100 error. while i have done all the steps such as re register dll files etc and it is still now opening.

Answer 1

The mfcdll100 error usually indicates you are missing the C++ 2010 redistributable.

You can install that from this link, ensure you install both the x86 and x64bit versions of the C++ redistributable, then restart (not shut down) your PC to apply the change.

https://www.microsoft.com/en-us/download/details.aspx?id=26999

Answer 2

The mfcdll100 error indicates a problem with the Microsoft Visual C++ runtime used by Adobe software, not with Microsoft 365 or Office. The available context only covers similar DLL/runtime issues in general and does not provide a specific, supported fix path for mfcdll100 with Adobe Lightroom.

Based on the context, the most relevant guidance is that such errors are typically caused by missing, corrupted, or misregistered runtime components (DLLs) and are usually resolved by repairing or reinstalling the dependent runtime or application. For Adobe products, this must be done using Adobe’s own installers and support guidance.

Because the error is specific to Adobe Lightroom and mfcdll100, and no Lightroom‑specific steps are provided in the context, no further product‑specific instructions can be given here.

---

References:

• Application crashing faulting module MSVC100.DLL - Microsoft Q&A
• "Runtime error 2147319779 (8002801d) library not registered" when setting a company as default
• Microsoft Office Access: 'Error in loading dll'
• Error message in Windows Vista when you try to install Adobe Acrobat or Adobe Reader: "The feature you are trying to use is on a network resource" or "Error 1714"
• Run-time error '53' - Microsoft Q&A
• Missing api-ms-win-core-winrt-l1-1-0.dll - Microsoft Q&A
• MVC140.DLL Error after Windows OS Updates - Microsoft Q&A