VST plugin not scanning on Vista/W7

Hello! We are currently in the beta testing stage of our product release. I've been compiling the plug-in on Windows 8.1 using Visual Studio 2013 Update 1 and the v120_xp toolset.

My beta testers are reporting that the plugin will not scan in any of their hosts on Windows Vista or Windows 7. Our plugin does not have any DRM, and we've been able to use it just fine on our Windows 8 computers. Multiple testers have confirmed this behavior, and it occurs across all hosts with both the 32-bit and 64-bit versions of our VST2 (not 3) plug-in.

Has anyone had a similar experience? I can't figure out if the plug-ins are scanning and failing quietly, or if they're really just not detected at all. Does anyone have a suggestion as to which host might provide the most detailed logs and how to reach them?

Also, any suggestions on the compilation side of things? Am I missing some sort of compiler flag or anything?

We're not using any dynamic libararies or anything that would show up as a missing dependency. We're just using JUCE and some of our own code.


Thanks in advance for any help!!

Okay, I figured it out. Our users' computers did not have the Visual C++ 2013 Redistributable installed. Thankfully this was caught during beta!