When installing FabFilter Twin, the installation program will try to copy the plugin into the common VST plugins folder (Windows) or the /Library/Audio/Plug-Ins/Components or VST folder (Mac OS X) on your computer. In most cases, your favorite host will then pick up the plug-in right away.
On OS X, this is the only possible location for a Audio Units plug-in (although you can install them in the user Library folders under ~/Library/Audio/Plug-Ins as well).
On Windows though, most hosts have their own VST plug-ins folder. So if you are using Windows and your host does not recognize FabFilter Twin, you need to locate the proper plug-ins folder for your host first (it is usually shown in a Preferences or similar dialog). Then, copy the file FabFilter Twin.dll from C:\Program Files\FabFilter\Twin to the plug-ins folder that you have found and restart the host so it can reload all its plug-ins. If you still have problems, contact FabFilter Support so we can help you out.
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