Hi Silmane-
Can you try the following?
1. Open Studio One, go to your VST preferences, and make sure "Scan at Startup" is checked.
2. Also click "Reset Blacklist" in the VST preferences, and then restart Studio One.
if that does not work, make absolutely sure that you installed the correct 64-bit or 32-bit version (depending on the version of Studio One you are running) to your VST folder.
Best,
Tom
