There appears to be an issue in Civil 3D 2012, and maybe other versions of the software, where it won’t let you create data shortcuts. The prompt that comes up informs that you must save before creating data shortcuts. Unfortunately after a save one still gets the error message.
One such cause of this error is corridors doing something automagically that causes them to change there status right after a save. It doesn’t happen to all corridor objects, just some of them. To get around this error lock the layer the corridor exists on. This prevents Civil 3D from changing the corridor’s state after a save.