Difference between vcruntime140d_app.dll and vcruntime140d.dll

问题

I'm unable to execute my Qt application because Qt5Widgetsd.dll depends on a vcruntime140d_app.dll, but my VS2015 installation only has a vcruntime140d.dll and I'm not able to find much information about vcruntime140d_app.dll on google. Does anyone know what the difference between the two are, why Qt5Widgetsd.dll depends on vcruntime140d_app.dll instead of vcruntime140d.dll and how I could get my hands on vcruntime140d_app.dll?

I have tried reinstalling VS2015 and running the vcredist installer in the Qt5.8.0 distribution.

Thanks in advance!

回答1:

The _app.dll is the C++ Runtime for store applications, while the normal vcruntime is for desktop C++ programs. The D stands for Debug version of the DLLs.

I can see the DLLs on my Windows 10 (1607) with installed VS2015:

Make sure you installed the VC++ tools and the Windows 10 SDK.

回答2:

According to my own experience, maybe _app.dll is used for UWP applications, whereas the other one is for ordinary applications. So if you installed the UWP support of Qt but didn't select UWP support when installing Visual Studio, you would encounter this problem. In order to solve it, I tried to reinstall Qt without UWP support, and after doing that, I successfully executed my Qt application. I'm not sure whether it is the exact reason but I hope it works for you.

来源：https://stackoverflow.com/questions/42341213/difference-between-vcruntime140d-app-dll-and-vcruntime140d-dll