did your door lock with the old barrel? try opening the door then push handle up to lock possition so theres nothing resticting lock to work correctly,then try and turn key,if it works ok your door needs toe and healing,if not your lock mechanism has failed and you need a new 1.hope this helps,feel free to e-mail me through my website with any more questins regarding this fault
shaun www.sdwupvcrepair.co.uk, March 2008