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Keep receiving this error message when trying to add new users. Only my phone as administrator will register. My wife and my sons phones will not register and get this error. They both used to be registered.
I have even deregistered the sure signal then reregistered it. Same still happens.. This has been going on for over 6 months so basically the box is useless.
Apologies that you're having problems adding additional numbers to your Sure Signal @drworld88.
So we can assist you further, please could you complete our Vodafone Sure Signal troubleshooting by following the Issue not listed option.
Copy and paste your results to this thread and we'll happy to investigate for you and help to get this resolved.