I have a TP on Metro that works fine. Have you tried deleteing the settings from the menu where you added the Metro connection?
Start-Settings-Connnections-Connections-Advanced (tab)-Select Networks- and then AutoConnect to internet connection select Sprint (or whatever has the Sprint settings-Edit-General(Tab) and Delete Settings
From the edit you can also go through each connection and reset them to MetroPCS settings. No registry edits should be needed.
I hope this helps.
Also, I'm attaching a MetroPCS settings cab (I know it says Mogul but it works)(i didn't make it. would love to give credit, but it's just I cabI now have)
Delete all of the connections that exist then run the cab the open IE and it will pop up asking you for your username & password (you can also edit the
modem in the connection the cab creates to
yourphone#@mymetropcs.com and pw: metropcs) I would try the above way first as the cab got rid of my battery indicator (I used advanced config seting Show Battery/Time to bring it back)
Hope this helps.