How to install multiple world versions from The Sims 3 Create a World Tool - Changing the WPID to give your world a different ID

When making a custom world with The Sims 3 Create a World Tool, it can be helpful to export and install multiple different versions. This guide will show you how to do that.

What is a WPID (World ID)?

When you create a new world in the Create a World Tool it is automatically given a WPID (world id) and this will remain the same as you work on your world, save it, export it and upload it.

This is how the game knows that the world you have made is the same throughout the process.

Why do we want to change it?

If you are working on a world, when you export it and install it into the game you can only ever have one version of the world installed at a time. Every time you make a change or update your world in the Create a World tool and export the world, you have to uninstall the previous world from your game.

Uninstalling also removes any save games associated with that world. This can be problematic if you're working or playing in an older version but want to test a newer version at the same time.

How do we create a new WPID?

Thankfully this is pretty easy, we need to open the .world file with S3PE and delete the WPID item. We can then generate a new one. Here's how.

Open up s3pe, if you don't have that download it here
Click File > Open and find your .world file. By default they are located in Documents > Electronic Arts > The Sims 3 Create A World Tool > UserToolData > Worlds
Once the .world is open ensure that both Names and Tags are checked in the Display section
Click on the Tag bar twice to sort the list. You should then see our WPID near the top.
Right click the WPID file and select Deleted. It will then strike out the line. You can now save the file and close s3pe
Now open your world in The Sims 3 Create a World Tool, when you try to Export your world now, you will most likely have the Invalid Package ID error. To fix this, select File > Save As and create a new save of your world.
Now you can Select World to Export and choose the newly saved world. This new version can be installed in your game alongside any previous versions.

Thanks to auntielynds's post from The Sims Creators' Consortium for sharing this solution originally. Unfortunately that website is no longer online so I hope this helps to share the information.