Oh, in that case it's more likely to be a drag & drop shell extension that is causing the problem.
You can use ShellExView to see which extensions are installed on your machine and try disabling them. Sort by the Type column and focus on the Drag & Drop Handler and Drop Handler extensions.
Remember that there could be more than one causing the problem (esp. if the Blue Soleil extension is still causing problems), so it might be best to disable all of them first and see if that fixes things, then try enabling a few at a time until it stops working again to narrow down which one(s) is/are causing the problem.