Scowcroft was released by Crystal Palace at the end of last season following 83 Championship appearances (14 goals) at Selhurst Park. Previous clubs include Ipswich (210 appearances, 48 goals), Leicester City (133,29) and Coventry (41,3).
Manager Williams told the Club's official website, "We've been talking to James about a transfer here for a while and I'm really pleased to add him to our squad."