Ucupaint Version
2.2.4
Blender Version
4.7.5
Operating System
MacOS
Describe The Bug
That's your Ucupaint add-on (v2.4.4, a texture-layering tool) — its unregister() tries to unregister a UI class that was never registered in the first place, likely because it only registers conditionally in interactive mode, but Unity launches Blender in headless/background mode for the conversion. The uncaught exception crashes Blender's exit, and Unity — seeing the process die abnormally instead of exiting cleanly — reports the generic, misleading "Blender could not be launched. Make sure Blender is installed and in your PATH" message. Blender is installed correctly and is on PATH; that message is just Unity's fallback text for "the subprocess didn't exit the way I expected."
Really annoying bug. It makes blender unsefull with unity
To Reproduce
- Install plugin
2.Open Unity
- Open Blender file and edit
- return to Unity
- blender file is not recognised
Disabling the plugin fixes the issue
In the case of a crash or when relevant include the logs
File ".../ucupaint/credits_ui.py", line 1048, in unregister
bpy.utils.unregister_class(cls)
RuntimeError: unregister_class(...): missing bl_rna attribute from '_RNAMeta' instance (may not be registered)
Ucupaint Version
2.2.4
Blender Version
4.7.5
Operating System
MacOS
Describe The Bug
That's your Ucupaint add-on (v2.4.4, a texture-layering tool) — its unregister() tries to unregister a UI class that was never registered in the first place, likely because it only registers conditionally in interactive mode, but Unity launches Blender in headless/background mode for the conversion. The uncaught exception crashes Blender's exit, and Unity — seeing the process die abnormally instead of exiting cleanly — reports the generic, misleading "Blender could not be launched. Make sure Blender is installed and in your PATH" message. Blender is installed correctly and is on PATH; that message is just Unity's fallback text for "the subprocess didn't exit the way I expected."
Really annoying bug. It makes blender unsefull with unity
To Reproduce
2.Open Unity
Disabling the plugin fixes the issue
In the case of a crash or when relevant include the logs
File ".../ucupaint/credits_ui.py", line 1048, in unregister
bpy.utils.unregister_class(cls)
RuntimeError: unregister_class(...): missing bl_rna attribute from '_RNAMeta' instance (may not be registered)