Hi Phillip, The issue was the same with all the adapters I tried - the laptop just wouldn't see the mount. I didn't know what was causing the problem to start with and it was only when a friend from my local stargazing group (Pig on SGL) came round with his kit that I started to get to the bottom of the problem. In the beginning I thought it might be a problem with my craptop, a very old 2005 Acer Ferrari, but his new laptop wouldn't work either. There just seems to be a compatibility issue with the chipsets in the adapters and the SLT mount. His Nexstar worked fine with his kit but mine wouldn't play at all. Once I followed the recommendations of others and bought the Tripp Lite adapter everything fired up straight away and I had my scope being guided by Stellarium. Try your USB-Serial adapter before ordering an alternative as it might well work for you considering yours uses Skywatcher's Synscan software but if it doesn't work then I'd recommend the Tripp Lite and hopefully you won't go through the weeks of pain and trips to the post office that I did. Dave Sent from my Nexus 4 using Tapatalk