Vst plugin using external dll not recognized by audio editors

Hello everyone,

I am new in this community and I hope my question is not redundant with another post.

I have made a first VST plugin following the tutorial by redwood audio (http://www.redwoodaudio.net/Tutorials/juce_for_vst_development__intro.html). 

It was a simple gain/pan for stereo audio. I tried it in audacity and Reaper. It worked fine.

Now, I am building a more complex plugin (Wiener filter). 

The problem I have is that the plugin does NOT appear in the plugin list (on audacity or Reaper), while it did with my first plugin.

It is not a problem of location of the VST plugin dll.

As I use a Fast Fourier Transform with the fftw3 DLL, I beleive the problem might come from this additional DLL. I am not sure of this.

Could anyone help me?

Could be that when loaded into a host, it can't find the path to this FFT DLL. When you're building VSTs it's always a good idea to statically link dependencies if you can, or at least to put the dependent DLLs in the same folder as your binary.