Effects have no effect

I can load an effect, such as reverb, or compression, or delay, etc. on an instrument such as a Halion synth or anything really, and the meter on the effect responds but there is no change in the sound of the instrument. I wonder if this is connected to the "VST library not found " message I get. I posted a couple of things about this but couldn’t get any response and I saw some posts about this and I tried to look at an article it says I already read it and won’t let me see the article. Please help, thank you !!