How to upload a custom server.jar file
Uploading a custom server.jar file can be useful when you want to run software that we dont have an "egg" for (support natively), so let's learn how to do it.
Remember, you need to be using a server egg that supports your respective software ( for example papermc for java, or nukkit for bedrock ). Follow this guide to change your egg.
This guide is for servers that run with a server.jar file, like Paper or Nukkit.
Connect to your server using SFTP. if you run into any issues with that, read this guide here.
Make sure you are in the root of your server files (/). You can see the server.jar in your server files already.

Navigate to where you have the new jar file that you wish to use on your server. In my case, I have it in C:\WitherHosting. Im using the Airplane Purpur branch as my custom jar file.

Rename the jar file to server.jar as we need to override the one that is already on your server.

Upload the file, and if it asks you to override a file that already exists on the server, click Ok/Yes.

Once the upload is completed, you can click start on your servers console, and it should load your new jar file!

If you get an error that is along the lines of Unable to access .jar file, make sure your jar is called server.jar, and if its still the case, follow this mini guide below.
Go to the "startup" section on witherpanel.com.

You can see in the above picture, that under variables server jar file is called wrongname.jar This means your server is trying to load that jar file instead of server.jar.
To change it, simply edit the text box to server.jar.

Your server should now be running the correct jar file. Open a live chat if you have any issues with this.
Remember, you need to be using a server egg that supports your respective software ( for example papermc for java, or nukkit for bedrock ). Follow this guide to change your egg.
This guide is for servers that run with a server.jar file, like Paper or Nukkit.
📂 Accessing your server via sFTP
Connect to your server using SFTP. if you run into any issues with that, read this guide here.
Make sure you are in the root of your server files (/). You can see the server.jar in your server files already.

Navigate to where you have the new jar file that you wish to use on your server. In my case, I have it in C:\WitherHosting. Im using the Airplane Purpur branch as my custom jar file.

Rename the jar file to server.jar as we need to override the one that is already on your server.

Upload the file, and if it asks you to override a file that already exists on the server, click Ok/Yes.

Once the upload is completed, you can click start on your servers console, and it should load your new jar file!

If you get an error that is along the lines of Unable to access .jar file, make sure your jar is called server.jar, and if its still the case, follow this mini guide below.
🤔 Truobleshooting - Can't find server jar 🤔
Go to the "startup" section on witherpanel.com.

You can see in the above picture, that under variables server jar file is called wrongname.jar This means your server is trying to load that jar file instead of server.jar.
To change it, simply edit the text box to server.jar.

Your server should now be running the correct jar file. Open a live chat if you have any issues with this.
Updated on: 22/02/2023
Thank you!