Lost keys

[Richie08]

Hi guy
I've lost both keys to my 2008 transit
Shes been off the road for a year now
I want to code a new key but when I re connect the battery the alarm goes off ,I do believe you can't code a new key with the alarm sounding
Has anyone had any experience with this ?
Thanks

[Frag]

Does it have the factory fitted Ford alarm (cat 1) ?
So,bonnet switch,and ultrasonic sensors in the lnterior light ?
Battery backed sounder