Reparar 2025 el error mfc120u.dll en Windows 10 y Windows 11: guía paso a paso

Summary

That dreaded mfc120u.dll error can bring your work to a sudden halt, leaving you staring at a frustrating crash message. Whether you’re on Windows 10 or Windows 11, this common issue often stems from a missing or corrupted file essential for many applications. But don’t worry—fixing it is simpler than you think. Our straightforward, step-by-step guide will walk you through the most effective solutions, from quick reinstalls to safe manual replacements, to get your software running smoothly again. Let’s resolve this together.

Método 3: Reemplazar manualmente el archivo DLL

When the previous methods—reinstalling the application and repairing the Visual C++ runtime—fail to resolve the issue, a more direct approach is required. Method 3 involves a manual replacement of the DLL file. This is a powerful but slightly more advanced technique that should be used with caution. It’s particularly useful when you suspect the specific mfc120u.dll file on your system is corrupted beyond what a standard reinstallation can fix, or if you are dealing with a portable application that doesn’t have a standard installer.

The core principle is simple: you will download a fresh, authentic copy of the mfc120u.dll file and place it in the correct directory where Windows and your applications expect to find it. The critical step here is ensuring you obtain the file from a trustworthy source to avoid introducing malware onto your system. The only truly safe source is the official Microsoft Visual C++ 2013 redistributable package, as extracting the file from it guarantees authenticity.

Here is the safe, step-by-step process for a manual mfc120u.dll replacement:

1. Identify the Correct Version: The file must match your application’s architecture (32-bit or 64-bit). A 32-bit program requires the 32-bit DLL, which belongs in the C:\Windows\SysWOW64\ directory. A 64-bit application requires the 64-bit version for the C:\Windows\System32\ folder. If you are unsure, replacing both is a safe bet.
2. Download from the Official Source: Instead of searching for the DLL directly on dubious websites, go to the official Microsoft Download Center and get the vcredist_*.exe file for Visual Studio 2013.
3. Extract the DLL (Optional but Recommended): You can use a free tool like 7-Zip. Right-click the downloaded vcredist_x64.exe (or x86), and choose “Open archive” or a similar option. Navigate through the embedded folders to find the mfc120u.dll file and extract it to your desktop.
4. Stop Related Processes: Before replacing the file, ensure the affected program is completely closed. For a thorough job, open Task Manager (Ctrl+Shift+Esc) and end any tasks related to the software.
5. Take Ownership and Replace:
   • Navigate to the target system folder (System32 or SysWOW64).
   • Locate the existing mfc120u.dll file (if it exists), right-click it, select “Properties,” go to the “Security” tab, and give yourself “Full control” (this is the take ownership step).
   • Copy the new, authentic DLL file from your desktop and paste it into the folder, choosing to replace the existing file if prompted. You will likely need administrator permissions for this action.
6. Restart Your Computer: A final restart ensures all system processes recognize the new file.

Critical Security Warning: Never download DLL files from random “free DLL” websites. These are often outdated, bundled with adware, or could contain malware. The only safe method is to extract the file from the official Microsoft installer, as described.

This manual method provides the ultimate level of control, directly addressing a corrupted file. With the DLL correctly in place, your application should launch without the dreaded error, successfully concluding our mfc120u.dll Windows 10 11 repair guide.

Conclusion

By following this step-by-step guide, you can effectively resolve the mfc120u.dll error and restore your application’s functionality. The outlined methods, from a simple program reinstall to a manual file replacement, provide a clear path to a solution. For a lasting fix, remember to always download replacement DLLs from official sources to avoid security risks.