Hey
I bought 2 kinect sensors and When I open ipi record, it detect only one camera !
And I saw in "dual kinect insallation guide " important note :

Important! Each Kinect Sensor must be plugged in through separate USB controllers. If both Kinects are plugged in through one USB controller then the second Kinect will not work. How it looks in the Device Manager:


But i'm not understand !

I conncet the first camera in the back of pc and the second one in the front !! put it's not working !!

Hello.
Look at Kinect devices in the Device Manager (Start Menu > Computer (right click) > Manage > Device Manager). If there is a yellow exclamation mark besides one of the devices, that means it does not work properly. Mostly often because both Kinects are in the same USB controller. You say you connect one to the front, and other to the back of computer. Yes, usually front connectors and back connectors are from different USB controllers, but your case may be an exception. Try all USB back connectors for one Kinect and then all front USB connectors for second Kinect, while watching for a yellow exclamation. If it doesn't help, may be your computer has only one built-in USB controller (this is common for relatively old staff or laptops). In that case, you will need an external USB controller.
See additional details in our wiki: http://wiki.ipisoft.com/USB_controllers