That is actually a Windows dialog and I think the server is the OLE server. Did you use drag and drop for copying? I am not sure if that denotes a flaw in the program or not. Florian, maybe this helps: http://support.microsoft.com/kb/248019/en
It seems not fixed - in V2.39c, if I SHIFT-drag top copy 394 files into Windows Explorer, after about 150 files (1min) I get the dialog box
. Server Busy
. --------------------------------------------------------
. This action cannot be completed because the
. "Milonga" program is not responding.
. Choose "Switch To" and correct the problem.
where "Milonga" is the title of the destination window.
Milonga is the title of the drag'n'drop destination Exporer window, and the folder that it is viewing. The source of the drag'n'drop, and of the dialog box, is mp3tag.