After installing the YouMail App, two contacts should now be in your phone:

YouMail Activate

YouMail Deactivate

Go to your contacts list and hit 'YouMail Activate' to connect your phone.

You can also dial the correct code below or click the code by visiting this page on your iPhone.

For AT&T or T-Mobile users:
Dial *004*9492652922# and hit send to connect

For Verizon users:
Dial *719492652922 and hit send to connect

For Sprint users:
Dial *289492652922 and hit send to connect