Squawkgear is deprecated and VATSIM doesn't allow it to connect anymore. You must now use Swift. It 's much more convenient and FlightGear is officially supported by it.
- You must use any FlightGear 2020.x or higher version to be able to connect with swift (via the Multiplayer>swift connection menu)
- download the latest
alpha version of swift
here (via other downloads).
- follow
this tutorial very carefully. (Some menus might look different as Swift has been developed a lot since the video was made, but the functionality is the same.
- more info
on the wikiEnjoy it!
Swift is way more complete than Squawkgear ever was (I've used both) and gives you a very immersive experience.
Edit: just a hint: I saw on the forums that you're a new pilot. Make sure you use an aircraft that you can handfly, land, know proper procedures, understand and use it's autopilot and have current charts at hand when flying on Vatsim (Navigraph is worth every €/$/£/¥ if you can afford it). I strongly suggest starting off at less busier airspaces (e.g. don't fly from/to London Gatwick during rush hour immediately). Also put a 'New pilot, first time Vatsim' comment in the remarks field of your flightplan. Vatsim controllers are helpful and kind most of the time, especially if you let them know you're new, but they do appreciate that you don't disrupt their operations or cause dangerous situations and have healthy judgement of what you're capable of
You'll see that you'll be very nervous to speak on radio the first time, but you'll get used to it fast and enjoy the very steep learning process you'll go through
Have fun!