Zte Imperial User Manual page 63

By default, your phone is configured to make Internet
calls, but not to ensure that you will receive them. But
you can configure your phone to listen for Internet
calls made to an Internet calling account you added
to your phone.
1. Touch the Home Key >
Settings > Accounts.
2. Check the Receive incoming calls check box.
Checking this setting will reduce your battery life
between charges.
> Menu Key >
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