So I bought this game to play online and it worked well. Until now.
Now I get the famous "busy freeze" whenever I go to multiplayer.
I've tried every possible fix:

Compability mode, hovering the mouse over cancel (although there's no time to do that really), verifying files via Steam, re-installing, verifying again, GameSpy fix (no servers), deleting galaxy.dll, stereomix fix, line-in-cable fix, etc, etc, etc, etc, etc.

I don't get why it worked up until now. If anyone knows of any fix, however crazy, please let me know.

I got it too.

Maybe the servers are down?

Same issue here, just freezes at "busy" while checking for multiplayer.

If this is a continuing issue, might have to contact GOG support about it.

Snap.
Can't even use task manager properly. Have to restart pc.
Anyone know if Game Ranger is worth trying these days?

It isn't. We should all just wait for GOG to fix this issue because it shouldn't take long.

GameMaster was discontinued over a year ago. I think you might be referring to SWBFSpy or something. Should also be mentioned that while SWBFSpy has better server stability, it is overall much, much less active like you said.

SWBFSpy is the GameMaster replacement of the GameSpy masterserver

See:

http://info.swbfspy.com/

I'm aware of that website. I help moderate their Discord server after all.