Multi-monitor failure with drag & drop enabled

[DougL]

Host and Guest are both Win-7 64-bit. Bi-directional drag-and-drop is enabled. Beginning immediately after booting, moving a file from desktop on primary monitor to secondary monitor works fine. Attempting to drag a file back from secondary monitor to primary causes screen lockup when transitioning across screen boundaries, even before releasing left mouse button. Clicking start orb brings up menu, which then becomes permanent on screen. CPU usage indicator looks like it goes to 50%. Session information shows disk read data continuously climbing. Inserting ctrl-alt-del brings up full-screen menu. Process monitor will come up if selected, but response is extremely slow. Switching users from ctrl-alt-del back to same (only defined user) comes back to black screens. Logout and then login from ctrl-alt-del menu clears the problem and screens are unlocked until trying to do another d&d from secondary to primary monitor. Enabling/disabling 2D and 3D acceleration has no effect. Switching drag-and-drop to host-to-guest solves the problem, while obviously losing guest-to-host functionality. I have been using a shared folder for years to move files back and forth between host and guest, so this is a very minor inconvenience. Other than, it took many hours to figure out why my shiny new 64-bit VM was locking up. I have not found any other reporting of this problem. Because this is a production machine, I did not test with a test version of VirtualBox. Please let me know how I can be helpful.