2000 Fiesta Zetec S, 1.6 Zetec SE engine, 105,000 miles, very good service history. Drivers door wont unlock so have to unlock using passenger door.

Drove to work on Friday evening as normal no problems, tried to start on sat morning and I have ignition lights and can hear the fuel pump priming but engine wont turn over. Initially thought it was a fooked starter but after replacing it the same problem exsists....???