UPDATE - This seems to be an issue specifically happening on Indifferent Broccoli hosted multiplayer servers. We're working with them now.
We can't connect to multiplayer with server and client both being updated, we're getting this error message:
File doesn't match the one on the server:
media/lua/shared/joypad/joypadsetup.lua
C:\Program Files (x86)\Steam\steamapps\common\ProjectZomboid\media\lua\shared\JoyPad\JoyPadSetup.lua
Even deleting the file and then doing a "Verify integrity of game files" and redownloading the file doesn't seem to fix the issue.
Server is verified to have updated to 42.16.3
Clients attempting to connect have been verified as running 42.16.3