This has already happened to some people. I don't remember how, but it can be fixed, so don't be stressed.
I can only help by pointing out that this thread seems to refer to the same problem as this one: http://forum.xda-developers.com/show....php?t=2773497
(also awaiting an answer)
Current phone: HTC One (M8)
HTC HD2 (Dec 2010 - Apr 2014; thank you Leo!)
HTC Touch HD (Dec 2008 - Dec 2010)
HTC Touch Cruise (May 2008 - Sep 2008 [stolen])
Previously: Nokia 6630, Nokia 3510