Followup on invalid panel path err. All test cases work now.

This is followup on my commit of 2014-08-27.
- c3 test case is passing. The case is app startup with panel saved path on removed USB drive. Funny dialog sequence shows up when both saved panels use the removed USB, though everything works.

- Fixed regression bug from the last change: not showing any message when attempting to enter inaccessible folder.