Problems with dual monitors - mouse switching Win7

I assumed she was placing the monitor and laptop side by side.  We got on the Intel graphics interface showing the two monitors and I said, "Is it like this?"  She said, "The external monitor is above the laptop".  Aha. There are some things  you can't see when you are in New York and your client is in California.
Thanks for all your help.  It led me to the correct solution.
Alan

How many remote people do you support. You should look into some sort of remote support tool. This will give you some eyes on the situation rather than relying on a user to be able to explain the situation.  

I have users call the desk all day saying my computer is not working, but in reality it is the one application that might be giving the user the problem. Once one of the support people connect to the user's computer they see it was just the app and not the entire computer.  

I use Microsoft Remote Assistance for internal support and use LOGMEIN Rescue for external support.  

Any remote support tool would have given you the insight you needed to resolve the issue.

I use teamviewer but that doesn't yet show me what the physical configuration looks like at the customer site.  I have used external webcams and Skype for that but the user's webcam is in her laptop.  
Thanks,
Alan