Today, I cannot observe the same “disallowed-drop” behavior by EmEditor on the same machine (Win7 Ultimate x86). So, Yutaka’s suggestion of restarting Windows seemed to have eliminated the problem.
But, if I remember correctly, I did reboot the system at least once and saw the problem persisting before I made the report. I had to make some extra efforts to prepare the illustration image (http://xxclone.com/img/dragdrop.png) to explain what I saw.
While it is easy to dismiss this episode as a semi “random” behavior of an unstable machine, the computer happens to be a very stable one which seldom goes to the blue screen. So, before I forget this story, let me document what was somewhat different from my routine EmEditor operations.
In retrospect, I was doing something that I did not do before. That is, before I observed the strange “disallowed-drop” behavior, for the first time, I started to use the the “Projects” pane in a new (to me) way. That is, until yesterday, I always used the Visual Studio (VS2010) solution file as the starting point.
Yesterday, for the first time, I started to use the “Project” scheme as opposed to the “Solution” scheme. Then, I realized it is more suitable for me to create my own set of files that are relevant to a given version of my “project”. Actually, I was delighted to discover EmEditor’s “Project” scheme (.eeproj in addition to the .eesln) which was new to me yesterday. Before I started to notice the “disallowed-drop” behavior, I was playing with the feature that relates to the .eeproj file (adding, removing the member files) for several hours as part of my work.
So, for now, let me report that the strange observation was noticed after considerable manipulation of the Project pane’s contents while doing my own editing session. Once I noticed the “disallowed-drop”, it did no go away, not even a reboot.
What I’m saying is that this may never surface again. But, I have a hunch that it may be related to the way EmEditor handles the .eeproj (or .eesln) feature.
Thank you for your attention. If I observe something more, I will make another report in this thread.