Hi JayOBrien-2384,
Please try the following steps:
Right-click your project and click Properties. Go to the "Publish" tab and click on "Application Files". Check the "Show all files" checkbox and scroll through the file list. Eventually, you will encounter a file with a yellow exclamation mark. This file is orphaned and needs to be deleted. Right click on the file and there should be a delete option.
(Or you can click the Reset All button.)
Then build the solution and the warning should disappear.
Best Regards,
Daniel Zhang
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