try flushing you cache, when i installed voukoder it at first didnt show up but then after i flushed my cache it showed up. but now i myself have a different issue that i get "Unable to start Voukoder Pro:" when i try to render. for me i use vegas so i just go to
C:\Users\Admin\AppData\Local\VEGAS Pro\18.0
and i rename the 18.0 version to something else like 18.0_test then the vegas will not use that cache
