You can't really fix this but if your game window is white its best to just wait. If you click in it game will freeze
This is propably happening because your pc fail to have minimum requirements.

If you dont see any servers when you refresh internet then here is what may be the problem
1. Game is just updated and there are no servers running that version of the game. Just wait a hour or two servers will start appearing.
2. Your firewall is blocking connections to servers. To fix this you need to go to your firewall or router settings and allow connections or something ( I dunno)
3. You have set some search filters. To fix change filters to



4. Make sure you click on internet not on local area network

To fix game crashing
1. uninstall all mods.
2. Reinstall the game.
3. Vertify the game files. ( In Unturned>Properties>Verify integrity of game cache

To fix error message when opening single player world you need to reset the world.
To fix stuck on loading screen find a way to kill yourself that will fix it.
Uninstall mods what you have been installed recently.

To fix this.
1. Restart game.
2. restart steam
3. steam inventory servers might be down at the moment.

If you have no gui (buttons) when you launch the game your graphic card is outdated. Update it!

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Also checkout my other guides!