Until now it was easy to configure Windows Mobile's settings, such as APN, using OMA CP (i.e: sending a .wbxml file using a WAP Push).
Since Window Phone 8, this solution does not work anymore because the security has hardened.
After reading the MSDN documentation it is still unclear about how to do it properly.
We added Trusted Provisioning Server and Push Proxy Gateway information into our .wbxml file. When the phone receive the SMS settings, a pin is asked. Once the pin has been correctly entered, a success message is received : "Phone's settings has been modified - Phone's settings update succeeded.". Whereas the apn did not change.
If anyone has some information we are currently stuck at this point.
EDIT : Worked on the case again. We used the app Field Medic to see the provisionning content written on the phone after our WAP Push. It's correctly changed but the settings of the phone are not updated. So I'm starting to ask myself; is OMA-CP really implemented on our test phone (Nokia Lumia 532 - Win 8.1) ?
Seeing the provisionning content and confirmation message from the phone does not necessary mean that the phone parameters are really modified apparently. I'm still investigating, in parallel to others things. If you have any advice or help to provide, thanks a lot.
Regards.