To resolve the error, follow the steps below: 1. Browse to the 'Releases' view in the Project. 2. Select the Release that you are working on. 3. Go to the 'Build' tab. 4. Change the 'Keep Unused Directories' value to Yes. 5. Rebuild the Release and test it.
This does indeed fix the error, but is there any way to find if i actually have 'Unused Directories' so i can remove them manually.