Are you trying to activate YouMail on an unlocked phone and getting an error message? Activating on an unlocked phone does not always work, but it really depends on the previous carrier it was associated with and the current carrier it is connected to. Unlocked phones often still have identifying data that indicates the original carrier/company the phone was associated with. When the YouMail app is downloaded to your device it will often identify that carrier as opposed to the carrier with which you are subscribed. However, there are instances when this should not affect activation.
If the phone was originally purchased from AT&T and then used with the T-Mobile network, you will have no issue activating YouMail as their activation codes are the same.
If the original carrier does not share the same activation codes (like an unlocked Verizon phone activating via Sprint Network), you will receive an error upon attempting activation. This error code typically shows up as an MMI code error.
In the case that you have issues activating, the only way to resolve this issue is to have your carrier activate call forwarding busy/no answer/unavailable to your YouMail mailbox number, also known as the Deposit number. To find your deposit number, go to the My Phones tab under Settings online. Look or scroll down to the How YouMail Works section. There, in bold, will be your number. Please ensure you talk to the advanced tech support department of your carrier network to ensure successful and efficient activation.
Here is how you may want to ask: Hello, I would like to setup call forwarding busy, no answer, and unavailable to this number please: *your deposit number*. (Please note that you do not want call forwarding ALWAYS enabled, as this will force all calls straight to voicemail)
Before disconnecting with the tech support team, make sure they give you a test call and ensure that only the missed/unanswered calls are forwarding to YouMail.
After doing these steps, there is no further action required to activate YouMail! Please remember that if you need to deactivate or are ever deactivated from YouMail, you will have to contact your carrier again to remove/reactivate this feature.