The very first google hit for LUMIA 900 BACKUP SMS has a very short and very clear answer. See for yourself in http://answers.microsoft.com/en-us/mobiledevices/forum/mdlumia-mdservices/how-can-i-export-backup-archive-sms-in-nokia-lumia/c6c51904-4456-4e87-9879-3371e552b5f5?auth=1.
It's "You can't. There's no way to transfer SMS."
Maybe you have more luck with other google hits?
Isn''t a phone with messages you can't mess with much better evidence that some printed copy from some backup?
Kees
Does anyone know how to backup the messages/texts from a Nokia Lumia 900?
This is my old phone and it is not currently activated (AT&T, Verizon, etc)
I need these text messages for a court case.

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