Follow one path...
When a file is read successfully on the Huygens Essential you can
1. do deconvolution: either press Start deconvolution directly to begin processing your image or first convert your dataset with the Tools menu. See Essential Deconvolution Roadmap.
If you have a Psf Distiller option in your License String, you can also...
2. distill a PSF: if you have loaded a bead image you also can select Start PSF distiller and proceed with generating a Point Spread Function from measured beads. See Psf Distillation Roadmap.