HumankindAssetFramework

Fix the Mod Editor `version.xml` error

Use this guide when the Humankind Mod Editor stops at Application Version with:

Something went wrong while loading the Unity project application’s version file: There is an error in XML document (2, 10).

This can surface immediately after a package import or update because Unity reloads the editor extensions. It does not by itself mean that HAF damaged the project or that the project needs a newer Unity version.

The failure

Open this file inside the affected Unity project:

Assets/Configurations/version.xml

In the known failure, its <Version> element contains a project path where the numeric Build value belongs. The bad attribute is:

Build="Development\Unity Projects\Amplitude.Mercury.Unityproject"

That line is legal XML, but the Mod Editor deserializes Build as a number. The path therefore produces the misleading “error in XML document” message.

Safe repair

Close the Unity project. This prevents another editor process from writing the file while it is being repaired.
Copy version.xml somewhere outside the project’s Assets folder as a backup.
Open the original Assets/Configurations/version.xml in a plain-text editor.
Change only the Build attribute to 0:
```
Build="0"
```
Preserve the existing Label, Major, Minor, Revision, and SerializationToleranceLevel values. Those values describe your installed Mod Tools/game version; do not replace the whole line with somebody else’s example.
Save the file as plain UTF-8 text and reopen the project with Unity 2021.3.1f1, the version targeted by the Humankind Mod Tools.

The repaired element may, for example, look like this — your other numbers may differ:

<Version Build="0" Label="NONE" Major="1" Minor="31" Revision="4836" SerializationToleranceLevel="10" />

The Mod Editor should now get past Application Version. If Unity was left open, use Assets ▸ Refresh; if the error remains cached, close and reopen the project once.

Optional verification in PowerShell

Replace the example path with the affected project’s path:

$path = 'C:\path\to\project\Assets\Configurations\version.xml'
[xml]$version = Get-Content -Raw -LiteralPath $path
[int]$version.Version.Build

The commands should parse without an exception and print 0.

Do not “fix” this by upgrading Unity

The official Humankind Mod Tools target Unity 2021.3.1f1. Opening the project in another Unity version can create an unrelated migration problem and does not turn a path into a valid numeric build value.

HAF is installed as a Unity Package Manager package under Packages; it does not ship or write Assets/Configurations/version.xml. Installing or updating a package can trigger the reload that exposes this project-file problem, but the reload is not proof that the imported package authored the bad value.

If `Build` becomes a path again

Do not keep repairing it blindly. Save these items before another reload:

version.xml before and after the value changes;
the exact package/update action that triggered the reload;
the first matching error and surrounding lines from the Unity Editor log;
the Unity version and the installed Humankind Mod Tools version.

That evidence distinguishes a one-time damaged project file from an updater that is actively writing the wrong value.

This site is open source. Improve this page.