Moonlite DRO focuser failed to connect

I have had a seemingly eternal issue with connecting my Moonlite focuser motor. The same error message EVERY time, but on the next try it works fine, what is the deal?
I have tried direct to the laptop and 2 different USB hubs(latest a Startech industrial 7 port and can’t get rid of the error on connect to the focuser.
I have a log file but can’t figure out how to link it.
Thanks ahead for any help on this.

You can share the log via dropbox (or similar) or create a support request via the help menu in SGP which will allow you to select and automatically attach a log.


I have the exact same issue.

What I have learned to do is to first select the “configuration” button next to the focuser drop-down. After a few moments, the Moonlite settings window pops up, and it will have found the focuser’s COM port. After that, SGP connects to it just fine.

However, like you, if I first try to connect to it, the message says it can’t be found. There’s some kind of initial search going on that usually works the second time. Or you can try my process if you’re tire of that error. Either way, it really needs to be better configured!

Interesting, may want to reach out to MoonLite as it sounds like this is some sort of issue with it finding the COM port or doing a search for the COM port. Can you set the COM port in the driver and avoid this searching behavior?

I have a NiteCrawler and it connects the first time every time. But I have specified the COM port in the ASCOM settings…not sure if that’s an option for their DRO or not.


I’m actually forwarding this along to Ron at MoonLite to get his thoughts…


To my knowledge, the COM port gets assigned and we don’t have control over which one.

I have given up on the Moonlite and going to the stock focuser and ZWO EAF but am still interested in the outcome of this issue.

COM port assignment is controlled by Windows upon connecting equipment. It could be that in your setup Windows assigns a different COM port after each boot up, or it finds equipment in a different sequences (or a different location given the usage of different USB hubs) and then assigns another COM port. This has caused problems for me in the past as well, but a couple of years ago I found this very helpful tool:

It allows you to assign fixed COM ports for your equipment. It can take some tweaking though before you are able to distinguish correctly between identifiers for each piece of equipment, especially when handling multiple cameras and mounts from the same computer. However, when that is done it will always assign the same COM port for each camera, mount and focuser. This then allows SGP also to connect to that equipment. It works for my Moonlite focusers as well and has not given me any of the problems described here in the past couple of years.