While following the device registration process, the user has to enter the UDID number of the device.
To find the UDID of a device - Connect the iPhone to a computer using USB, and then launch iTunes.
The page appears as shown in the following figure:
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- In the upper-left corner, select the required iPhone.
- On the left navigation menu, click Summary.
- In the right panel, click the serial number of the device to display the UDID.
The page appears as shown in the following figure:
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- From the right panel, copy the UDID number to use it while device registration.