If you need a USB-to-serial adapter...
I've had better luck with new FTDI-based adapters than older Prolific and older FTDI on Windows 10. Based on numerous anecdotal reports, the FTDI adapters seem more reliable in general.
These are what I use now: https://www.amazon.c...B004ZMYTYC?th=1
One nice thing about the driver for this one is that it retains its port number even when using different USB ports, which not all of them do (or did, anyway). At $20, they're only a few bucks more than the el-cheapo knockoffs.
You'll also need a 9-pin serial to Celestron adapter.
Here's one found at random: https://www.amazon.c...e/dp/B0000665UZ
I can't vouch for that particular one, but they're fairly simple and cheap.
Good luck! Stellarium works great with the AVX. Do remember to check the Jnow button when setting up the telescope. There's no need for ASCOM if you select Celestron NexStar as the device.
Edited by SkipW, 10 October 2019 - 08:45 AM.