The plugin is not being recognized by Reaper, which is my main DAW for professional use. I tested it in Cubase and, although the VST3 is detected, it does not load or open when clicked, as shown in the attached screenshot (VST3 on the left, VST2 on the right). I also tested it in Ableton Live 12 and the plugin loads normally in the VST3 version there — it only fails in other DAWs.

I have already completely uninstalled the plugin and reinstalled it both via Slate Digital Connect and manually. I also removed registry entries and reinstalled the DAWs, but the issue persists. The VST3 does not work, while the VST2 works fine. On Reaper and Cubase only the VST2 works, and on Ableton both versions works normally

 

Do you have Blue Cat Audio's PatchWork by any chance?

It could be worth trying to load the VST3 versions inside PatchWork in Cubase and Reaper, just to see what happens. That way you are manually loading them instead of needing the DAW scan to validate them.

If they work there, try closing and reopening the DAW and then loading the plugins without PatchWork. It would help you figure it out. Also, did you ever have them working in those DAWs as VST3 before, or are you just now installing them the first time?

 

Are all your drivers up to date? Are all runtime and .NET dependencies up to date? Have you installed any other software before this? What graphics card? What CPU? You can find out which events are not working properly in the Windows Event Viewer.