Before we get into activation steps and troubleshooting, let's see if your T-Mobile contract type allows for you to use YouMail.
For Prepaid users:
Unfortunately, most prepaid carriers, like Boost and T-Mobile, do not have the Conditional Call Forwarding feature enabled on these plans, which YouMail needs to work. We'd love to have you so we're upset too that your carrier places these limitations on you. If you are looking to switch carriers/plans, YouMail partnered up with Ting and we are now offering free $50 credit to Ting if you sign up through this link.
How to Activate YouMail on T-Mobile:
To learn how to activate YouMail through the app, please go to our How to Setup Call Forwarding with YouMail Help Center article.
T-Mobile MMI Error Issue:
As of October 16, 2019, we've found that some T-Mobile YouMail users are experiencing an MMI error. If you received a message that said "invalid MMI codes" please follow the following steps.
- Go to your iPhone's Settings app
- Go to "Cellular"
- Click "Cellular Data Options"
- Tap "Enable LTE"
- Click "Off"
- Return to the YouMail app and try to reactivate (open the app, select the Settings icon in the bottom right, click "Activate" and follow steps).
- Go to your Android's Settings
- Select "Network and Internet"
- Select "Mobile Network"
- Turn off "Enhanced 4G LTE Mode"
- Return to the YouMail app and try to reactivate (open the app, tap the Menu in the top left corner, go to Settings, click Activate/Deactivate and follow steps).
**Note: The settings choices may differ slightly depending on the phone and OS.**