Hi. 

In the last two weeks, I have successfully cooked around 10 separately built test projects in Unreal Editor2025.2.0 for Aximmetry. A few of those included Datasmith content and trees downloaded via Fab. I tried to cook another project today using only Datasmith content and the same tree assets. Cooking failed and the (very short) error log stated "Platform Win64 is not a valid platform to build. Check that the SDK is installed properly and that you have the necessary platform support files (DataDrivenPlatformInfo.ini, SDK.json, etc)"

Looking in the config files C:\Program Files\Aximmetry\2025.2.0_UnrealEngine\Engine\Config\Windows, I find Windows_SDK.json and other config settings files.

This project is no more complex than the others which successfully cooked, other than that there are many more trees (added using foliage tool) and exponential height fog added. Otherwise there is little difference.

Are there json files missing or is there any other simple explanation?