Land Rover Repair: Car dead, land rover discovery, 2003 land rover discovery

Question
I went out to my 2003 Land Rover Discovery SE today and it
was dead, I figured it was the battery due to the fact I've
never replaced it. When my road side assistance guy jumped
me off the M and S green lights on the dash and the D on the
drive shaft were all flashing. It was very difficult to
accelerate, so I dropped it straight off at my mechanics.
What does this mean? Thanks

Answer
It sounds like the vehicle's computers may have gotten messed up by the power failure and subsequent attempts to jump it and fit a new battery.  If the M and S lights continue to flash and the D light on the instruments flashes you will need to find a Land Rover specialst with Autologic or T4 equipment to sort those systems out.  My guess is, the perceived lack of power is actually the transmission stuck in third gear and not shifting.