Updating the SDK

If you need to update your SDK, it is important that you follow these steps to ensure the update proceeds properly and you don't have any old/conflicting files.


Migrating from Unity 2017 to Unity 2018

If you are migrating an old project from 2017 to 2018, you MUST follow the instructions given in Migrating from 2017 LTS to 2018 LTS.

Version Control

If you know how to use it, you may find it beneficial to use version control software like Git to manage your project. You don't need to upload your repository to Github or similar service to gain the benefits of version control. Create a commit before you upgrade SDKs just to be sure.


For SDK3, you should be able to update in-place. This is especially important for SDK3-Avatars, as you may lose State Behaviors on your animators if you incorrectly update!

If you want to be super careful, always back up your projects before updating the SDK.

SDK3 - World

If you are upgrading from a post-2020.3.2 SDK3, you can import the new package over the old one. If you run into issues, please try reinstalling.

Pre-2020.3.2 SDK3 Upgrade Process

If you are upgrading from the pre-2020.3.2 SDK3:

  1. Close Unity.
  2. Back up your Unity project! You don't have to backup your Library folder, these files are auto-generated by Unity.
  3. In Assets/, delete the VRCSDK folder and the Udon folder, along with the associated meta files.
  4. Open Unity.
  5. Import the new SDK3 - World package.

SDK3 - Avatars


Do not perform "Deletion Reinstalls" For SDK3 - Avatars!

If you delete the SDK folders with Unity closed and open Unity without the SDK installed, you will lose State Behaviors. They are fragile and do not persist through full deletion upgrades. Make sure you back up your projects often, and save/document your state behavior setups.

If you must perform a full deletion reinstall of your SDK3 - Avatars package, back up your project first. You will have to set up your State Behaviors again, so ensure you have documented them well.

  1. Close Unity.
  2. Back up your Unity project! You don't have to backup your Library folder, these files are auto-generated by Unity.
  3. Open your Unity project.
  4. Import the new SDK3 - Avatars over the old one.

SDK3 - Avatars - Separate Project Process

If you run into issues with upgrading via the above process, try this instead:

  1. Close Unity.
  2. Make a new, blank project.
  3. Import the new SDK3 - Avatars package into that project.
  4. Close that Unity project.
  5. Using Explorer (Do not open Unity yet!), delete the VRCSDK3 folders from the project you're upgrading. Until this guide says otherwise, do not open Unity.
  6. From your new blank project that you imported the SDK into, copy the VRCSDK3 folders into your project that you're upgrading.
  7. Once the copy completes, open your upgraded project. You may delete the blank project.


Here's how you update VRChat SDK 2. If you're just uploading avatars, you can use the following process:

  1. Please ensure you're using the correct Current Unity Version.
  2. Download the latest version of the SDK. See the Choosing your SDK page to see how to choose the correct SDK for your use.
  3. Close Unity.
  4. Find your Project folder with Windows Explorer, and find the Assets folder.
  5. Delete the VRCSDK folder, as well as the VRCSDK.meta file in the Assets folder.
  6. If you are using SDK3+Udon, delete the Udon folder, as well as the Udon.meta file.
  7. Relaunch Unity, and then re-import the freshly-downloaded SDK. Do so by going to Assets, then Import Package, then Custom Package.
  8. Select the new SDK (you probably saved it in Downloads)
  9. Wait a moment, and click "Import" in the bottom left. If any files in the list are greyed out/unchecked, and you can't check them, you didn't delete everything you should have! Start over.
  10. Wait a minute as the SDK finishes importing.
  11. In each scene, enter Play mode, and then end Play mode. You may receive a message from Unity that it needs to update some parts of the scene. Follow those instructions, and then restart Unity.
  12. Done! You should be good to go.

Advanced Update Process

If you're reinstalling the SDK in a project that contains a world using complex trigger setups, here's a safer way to update your SDK.

  1. Close Unity
  2. Back up project to another folder (do not back up the Library folder, these files are auto-generated by Unity)
  3. Delete SDK and Plugins folder, as well as the the associated .META files
  4. Create a new dummy Unity Project
  5. Install the latest SDK on the dummy project
  6. Copy the newly added SDK/Plugin and associated .META files from the dummy project into your original project
  7. Done. Now you can open your upgraded project, and there will be no crash no matter how complex your trigger work!

Updating Unity

If you are updating from a previous version of Unity, we have a guide for updating to our latest version we support! Check out the relevant page below:

Migrating from 2017 LTS to 2018 LTS

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