SMS syncing problem

[MassDeduction]

I've successfully synced SMSs to my Microsoft Account/OneDrive from all sorts of devices. Lumia 920, 1520, 635, you name it. My Lumia 1020 won't sync my SMSs to OneDrive, using the same Microsoft Account and the same settings. Is there likely an offending SMS I need to delete? I'm at a loss. Any thoughts appreciated.