Errors exist for one or more children

After changing an orchestration only little, the build process sometimes throws an exception that says "Erros exist for one or more children". This message seems a bit random, since I couldn't find a real problem, like a missing assembly, definition, or port.

In my case, it helped to recreate the construct shapes from the orchestration by deleting the shape, creating a new one, and adding the code of the deleted one. After that, the error disappeared.

PS: You can even find the error message also inside the orchestration file. It might help to watch the changes inside the code, while you modify the orchestration in the orchestration designer. This way, you get a feeling of how BizTalk creates the code from the designer, and you can also observe when the error disappears.