"File could not be opened" message during layout work in FM12 converted file
I have a data-separated solution I converted from FM11 to FM12. Everything works fine. However I find that when in layout mode, if I ask Inspector to show me, for instance, the Tool Tip for a given field (or the Data source for a given field), I am greeted with a File Cannot Be Opened error message. That message references my data file. The layout I'm in is in the UI file. I get a file open dialog which I can either dismiss (press Cancel) or select the data file (press Open). Either way, the problem goes away for the remainder of the session for that and all other layouts in the UI file. This will happen all over again the next time I load the solution and go into layout mode and do the above.
My external data sources are all defined well. I have another converted data-separated solution that doesn't have this problem. I don't see what the difference is.