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Install Visual Studio Express 2013 from https://www.visualstudio.com/vs/older-downloads/. We recommend this version of Visual Studio because it is the same version used to compile OpenSim itself. However, obtaining Visual Studio Express 2013 is no longer very easy; you must have a (free) "Visual Studio Subscription". In some cases, you may be able to get away with using Visual Studio 2017, from https://www.visualstudio.com/vs/. In particular, the Depreciated_CPP_From the Ground Up: Building a Passive Dynamic Walker Model example works with Visual Studio 2017.
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