Notification kills mouse/keyboard interactions on remote desktop session

[BoundaryValueProblems]

When I connect my windows machine from my mac via ms remote desktop, and check my gmails using firefox on my remote windows machine, normally it's fine and works well. However, when a new email arrives and notification window shows up in the right bottom part of the windows screen, somehow, I lose control of any interactions via mouse/keyboard. This of course happens only using the remote desktop. If I work directly on my windows machine, there's no problem. I am wondering what causes this problem. Thanks! BVPs