The exception in the server tick loop error will prevent your server from loading and deny you access to your game. The good news is that the following error is not one without a solution. Read on from our programmers on how to solve this issue.
Method #1: Review Server Files
The first step is to review your server files to ensure none of them is missing, especially the JSON document.
You can do this by using the web-based FTP client which allows you to manage your Minecraft server docs. Navigate to FTP file access and log in using your dedicated panel password to review your docs. Once it accepts, they will redirect you to the home directory of your server.
Step #1: Stop the Server
To bring your server to a halt, you can use the /stop command. This will end your server activities and save all the data. This includes worlds, chuns for the Overworld, players, etc. This command will help prevent crashes and lags.
Step #2: Access Your Server's File Manager
To access your file manager, you have to press the WIN+R key, then type in% APPDATA% followed by the OK button. If you follow this process well, the AppData folder will open; scroll down to locate a folder with .minecraft. This will contain your server details.
Step #3: Delete Json Files
After reviewing your server docs, find out if a file is missing or invalid. Then, delete the invalid .json files and replace them with the corrected ones. This will fix the tick loop error issue, and prevent it from happening again.
Step #4: Start Your Server
It’s time to re-start the servers. Once done, everything should be back to normal.
Method #2: Delete server.toml files from the serverconfig folder
Another way to fix the exception in server tick loop error again is to delete the server.toml files. Do this from your config folder. Select the server and scroll through to the left side menu to access your config document to select Config Files. Once the config file is open, delete the server.toml files.
Method #3: Check if You're Using an Updated Version of Optifine
Another surefire way to get the exception in server tick loop error fixed is to use the updated version of Optifine.
Minecraft servers are delicate and can crash  while you play and prevent a server from loading. You can find an answer helpful to solve this particular issue in this guide. Make sure to follow the solutions’ steps properly.