Hopefully this tip will save you an hour of debugging. I was working with the NativeDragManager in an Adobe AIR app and I couldn’t get my application to accept an image file being dragged from the file system. The reason was due to the elusive Windows 7 “Run as Administrator” setting.
I had opened Flash Builder 4 in administrator mode by right-clicking on the shortcut and choosing “Run As Administrator.” I do this anytime I’ve installed/updated Flash Builder because it often needs to do some fancy system stuff to complete an installation. Because it was in administrator mode, when I tested my AIR application, it was in administrator mode too. My application would not accept any files from a non-administrator place (i.e. the desktop).
To fix the problem, I closed Flash Builder and reopened it as a normal application. When I tested my AIR app, everything worked fine.