Hi kross, Paul + Mike, After changing the port to 4400 and saving, it returns to 0 ! This doesn't prevent the use of PHD2 but the error remains. When you talk about "nightly build" , you mean that you downloaded the last code and compile it ? I'm afraid I can't do that. I find also the new Internal Guider improvements very impressive and so easy to use. Thanks again !!! The reason I wanted still to use PHD2 is because the GPG RA Guider asks for the Major Period . How do I get it ? My idea was to use PHD2 : Brain / Algorithms / Predictive PEC : is Period Length (PHD2)= Major Period (EKOS) ? Finally, I would suggest an improvement about GPG RA Guider. This is a long dialog which needs to be scrolled . But scrolling with two fingers on a trackpad might change the fields values without notification. This is really annoying and I suggest to inhibit that field property.Read More...