Car won't start; mechanic said it was fuel pump; fixed problem but car still won't start...any suggestions of what could be?

If the fuel pump works, the Relay is Working. But I have never herd of a corsa comfort

You are right that it could be either component, or something else electrical. The security system will kill the fuel system if the wrong key is used or the system is acting up.
A mechanic would check base fuel pressure with a gauge and also see if the pump is getting power from the relay when it fails to start.

Relay, on top of fuel tank under parcel shelf, check its getting power, if not its fuse, if it is, bin it get a new one.

If you have checked fuel pressure with a gauge and the pressure is normal, are you getting spark to the plugs ?

If this is a diesel engine you probably have an air lock in the fuel system. It will need "bleeding" before it will start. If you have already tried bleeding the fuel system there may be an air lock in the injectors. If it still doesn't start I suggest you carry out a compression check because diesel engines need to be in good condition to start easily, especially in cold weather If it is a petrol engine, there could be problems with engine timing or ignition problems.

I assume the pump was replaced because it was getting power but no fuel pressure ?
Are you still not getting fuel pressure ?
Spark to the plugs ?
Normal compression when cranking the engine ?
Security light not staying on ?

I suggest you try one of those instant download manuals. My brother ( a mechanic) buys
it when he can't fix some technical issue He buys from www.reliable-store.com . A lot of mechanics actually do this. Website is very good for this. Must try it !!

check fuel pump relay

ricks63toy, I believe that Ford still uses what is called an inertia switch even in the hybrids. This switch will shut off in the event of an accident shutting off the fuel pump. This is a safety feature built into the vehicle. Seeing that this is a newer vehicle I trust that you still have the manual. If not, the switches are usually located in the trunk. Look on the side walls of the trunk and see if you can locate it. It is usually marked by a sticker. When you find the switch, push the red button down until you hear a click. This will reset the switch and allow power back to your fuel pump. Good luck with this.

When it ran out of fuel there may have been damage to the fuel lines. I would suggest getting it looked at by a mechanic to be safe