Don't know but I don't think it's the phone. I have been following a few post and it seems to be with Verizon because I've been getting the error message for a few weeks now on my Commando, I figure I'll give them some time before I contact them.
I want to assist in ensuring your contacts are safely backed up! Are you getting this error message when initially setting up Backup Assistant, or trying to manually sync new contacts on the phone? Do you have your contacts set up as Google contacts? If so, they will not back up to Backup Assistant. I recommend starting under Settings, go to Applications>Manage Apps>All> Backup Assistant, then tap 'clear cache' and 'clear data', after reboot the phone and retry to application. Keep me posted!
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