> For the complete documentation index, see [llms.txt](https://docs.engagevr.io/developer/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.engagevr.io/developer/readme/upgrading-to-unity-2021.md).

# Upgrading to Unity 2021

As part of the ENGAGE v3.3 release, we upgraded the ENGAGE application to Unity 2021. If you had an SDK repository at that time, we also updated it to Unity 2021 and pushed those updates to the GitHub repository; unless you indicated that you wanted to perform the update yourself.

However, you still need to upgrade your local development environment to Unity 2021. To do so, complete the following steps:

1. Complete the steps described in [Installing the Unity Editor](/developer/setting-up-the-engage-sdk/installing-the-unity-editor.md) to install Unity Editor 2021.3.37f1.
2. Pull the updated project folder from GitHub.
3. Open Unity Hub, and then, from the side menu, select **Projects**.
4. For your project folder, select the version number listed in the **EDITOR VERSION** column.
5. From the **INSTALLS** list, select **2021.3.37f1**, and then select **Open with 2021.3.37f1**.
6. Confirm or agree to any prompts related to updating the project.

{% hint style="info" %}
If you don't use Unity Hub, at step 3 in the previous instructions, open Unity Editor 2021.3.37, and then open the SDK project from within the Unity Editor.
{% endhint %}

{% hint style="warning" %}
You must rebake all lightmaps in your scenes. Otherwise, colors will appear faded.
{% endhint %}

If you have any issues with the update process or experience graphical anomalies that you can't resolve, please [contact support](https://support.engagevr.io/).


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