Specify first corner problem

[Peter.deVries]

I do not know when it first started, but I have encountered this issue on and off. This is my problem. When working on a drawing within Autodesk Map3d2010, everything is working just fine. But after a while, specifying the first corner in the Zoom Window command behaves quite strange: when I specify the first corner, AutoCAD snaps to the Lastpoint and prompts me for the other corner. It is not just a graphical issue, but AutoCAD really uses Lastpoint as input for first corner. When I switch to another drawing within the same AutoCAD session, specifying first corner works just perfectly. So it does not seem to be registry or application related. The only solution to this problem is to save the drawing and reopen it. But after a while, the problem reoccurs. I really hope that one of you recognize my problem and - more importantly - knows how to fix it. My spec are: - Windows Vista 64bit SP2 - Memory (RAM) 24,0 GB - Processor: Intel Xeon CPU E5540 @ 2.53GHz - Autodesk Map3D2010 64bit - Pointing device: Wacom Intuos3 Tablet, driver version 6.3.3-4 Please help me find the solution to this annoying problem! Kind regards, Peter de Vries Royal HaskoningDHV Netherlands