Re: Why can't I unlock KOA Omniblade Daggers in ME3 demo?
You can't connect to EA server through the ME3 demo, because the demo isn't up to date anymore.
There was a validity period for the multiplayer (and so for servers) of this demo:
Chris Prestly answered this :
"How long will the demo be available?
The multiplayer section of the demo will be deactivated March 5, 2012 The single player demo will continue to be
available past game launch (for a number of months – exact date for the demo to be taken offline is TBD)."
But, normally, if you finished it (before the 5th of March), you probably received it in something called "Special Delivery chest".
I think if EA servers aren't available anymore, they can't receive the information that you finished the demo, so if you've played it recently, I suppose you won't be able to obtain it...