In order to configure your MMS settings, we advise our Vikings to go to the next setup guide first. Select the manufacturer and the specific type of device you’re using. Afterwards, you may follow the manual configuration of the MMS settings. You can’t send MMS anymore. But you can still receive them via an url you’ll receive via text message.

When your MMS isn’t configured yet, you’ll receive an SMS instead with a password and a link to a website. You’ll have to log in on this website by using your phone number as username. Enter 324… instead of +324, 00324, etc. The password can be found in the text message you’ve received.
If it’s not possible to check this website via your smartphone, it should be a better option to go do this on a PC instead. An MMS will be valid on this website for one month. Afterwards, it isn’t possible anymore to log in to watch the message.