Effects not visibel in AfterEffects

I reinstalled AfterEffects CS 5.5 ,and then ParticleIllusion for Aftereffects , with the pIAE_Win_102_installer ,
that I have for many years - it always worked out , but this time the effect are not visible on the work ,
though they are visible in the “select emitter” .
I repeated the installation again , but the same problem again …
What can be the reason ?
Exuse my poor EnglishLanguage …