Run these commands in an elevated Command Prompt:

If you have encountered an error message referencing "qmsl-msvc10r.dll", "39-qmsl-msvc10r.dll-39", or a similar variation, you might be concerned about system stability, malware, or broken applications. This article explains everything you need to know about this file: its purpose, why errors occur, and step-by-step solutions. qmsl-msvc10r.dll is a Dynamic Link Library file associated with QMSL (Quick Measurement Software Library) or similar measurement/data acquisition software. The "msvc10r" part of the name indicates that it was compiled using Microsoft Visual C++ 2010 Redistributable (the "r" stands for Release version). Breaking Down the Name | Component | Meaning | |-----------|---------| | qmsl | Quick Measurement Software Library (likely from National Instruments, Keysight, or a similar instrumentation vendor) | | msvc10r | Microsoft Visual C++ 2010 Redistributable runtime | | .dll | Dynamic Link Library |

Remember: The unusual 39- prefix/suffix in your search query is not part of the filename. Focus your troubleshooting on qmsl-msvc10r.dll , and always obtain it from trusted, official sources. Last updated: October 2025. This article is for informational purposes. Always consult your software vendor’s support documentation for hardware-specific guidance.

The only safe source is the original software vendor (Keysight, NI, Rohde & Schwarz, etc.) or your original installation media.

Below is a comprehensive, long-form article that explains what this file is, where it comes from, common errors related to it, and how to fix them. Introduction In the complex ecosystem of Windows operating systems, DLL (Dynamic Link Library) files play a critical role in allowing software applications to share code and resources. One such file that occasionally raises questions—especially among users running legacy or specialized software—is qmsl-msvc10r.dll .

The actual DLL in question is most likely .