Default Unable to Flash Rom?

I'm using TWRP v2.6.3.0, I've tried Factory Reset and Advanced Wipe (Ticking off Dalvik Cache, data, System, cache). Then I go to install a rom, it gives me an error. I currently don't have another camera to show the error. I'll write what I see in the terminal:

set_metadata_recursive: some changes failed
E:Error executing updater binary in zip'/extern(not sure what's after this, it doesn't show).
Error flashing zip '/extermal_sd/cm-11-20131222-
Updating partition details...

And that's it, I don't know how to fix it. I've tried everything.

I'm using i727r by the way, not the AT&T version.

-John.