The Project ID settings, Generate and Invalidate, do not change the Project ID.
1. Launch: UE4Editor.exe (any project)
2. Project Settings > Description > About
3. Click the down-arrow beside the Project ID field
4. Select Invalidate
5. Select Generate
Neither the Invalidate nor the Generate options have any effect. In a converted project, the old ID remains the same and is not invalidated or regenerated, and in a new project the ID remains all zeroes.
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