A customer wanted to know how to enable a confirmation dialog whenever the user inadvertently perform a drag/drop operation in Explorer to move files within a volume.

For example, if I have an S drive mapped to \\server\share, I would like to display the confirmation dialog when users inadvertently drag and drop a file or folder within the S drive.

Okay, first of all, the problem statement doesn't match the question. But that's good, because the question was misguided.

The question was "How do I add a confirmation dialog to every drag/drop operation?" But the problem statement was "We have users who inadvertently drag and drop files."

So they didn't actually want the confirmation on every operation; they only wanted it on the accidental ones.

Of course, the computer can't read your mind, so it doesn't know what you were thinking when you performed a drag/drop operation in order to determine whether the operation was intentional or accidental. The customer asked for a dialog box to appear after every operation just in case it was inadvertent. But since most actions are intentional, the result is that users get confirmation dialog after confirmation dialog. Soon, dialog fatigue sets in, and users just get into the habit of ignoring them.

But let's go back to that inadvertent adjective. The way to reduce the likelihood of accidental drag/drop operations is to adjust the drag sensitivity so that the mouse must move a "significant" distance before a drag/drop operation is initiated. What constitites a "significant" distance is something you can choose based on your own experiments.