This error is affecting all Unturned servers as of tonight and may be fixed with tomorrow's update.
In order to fix this issue, you must do the following:
- Open Unturned
- Click on Survivors
- Click on Inventory
- Dequip all cosmetic (mythicals and non mythicals) items from your character
- Try joining the server you wish to play on
- If you are still experiencing issues, try the following: Go through your Survivors->Inventory, hold CTRL and double click on all cosmetics and skins on each page (https://www.youtube.com/watch?v=rucYU_toV0Y)
- If you are in the Steam Beta, opt out of it in your Steam Settings
If the problem persists, through each page of your items list and check if you have each item equipped, individually. After unequipping them, you will be able to join Unturned servers. You have to unequip all your cosmetics and make sure of it.
Also ensure you remove all your cosmetics from ALL your characters (if you have the gold version of Unturned).
We hope this fix works out for you guys.
Thank you all for your patience and understanding.