The front derailleur won't go out far enough?

1-pull the chain off.
2-undo the FD cable.
3-sight down through the FD cage at the crankset. It should be in all the way.
4-back off the limit screws quite a bit. You should be able to see if they're touching the cam inside them.
5-make sure it "rests" in far enough to guide the chain over the small front ring.
6-push it out with your hand to see if it moves out far enough to guide the chain over the largest front ring.

If it won't go out far enough with the setting screws backed out, next step is to check how it's mounted on the seat tube.
Make sure it's above the largest ring with clearance for the outside of the cage to clear it by 2-3mm.
Make sure the cage is aligned with the chain rings longitudinally. Make sure the FD is not bent.

If it's aligned and can clear the big ring, and the setting screws are backed out, check the crankset.
The crankset may not be on far enough.
The bottom bracket spindle may have been replaced.
The chain ring may have been replaced.

If it still won't clear the large chainring, you could have a bent frame, but that area is pretty darn strong.
To me, it may be more likely that the FD is the wrong model, or has some flaw that is limiting it's movement.

If it won't clear the rings by hand, with no chain, don't bother with the cable or chain.
You've likely got a bigger problem, most likely the FD, which is a $20 fix on that bike.

If it does clear the outer ring once you've checked everything, reattach the cable (without the chain).
Now do the shifting to see if it still works, and clears the chain rings.
If it does, install the chain, adjust the inner and outer set screws, and ride.