Thanks for your help everybody - I did get SEtool2lite and it helped - I actually found the answer at this link though
http://www.akshayy.com/sonyericsson/tutorials/red-light-blinking-dead-revive-it-to-life

I noticed when fitting the battery back that a small red light blinked 5 times - using the link aabove gave me the answer - use setool2 lite as described and it works a treat

well done to the online community !!!