1. On the Solution Explorer tab, right click the missing PLC Project and remove it.
2. On the Solution Explorer tab, right click the PLC level and select “Add existing item...”
3. Browse your project folder, select the “PlcProject.plcproj” and open it.
4. With that, you should be able to see your project PLC again (similar to the image bellow) and the Export shuold also work.
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