Recording on Eurovox ex5100?

I have just got the above and when I try to record I get an error message saying "hard disk is full or not installed". When I try to go past this and record it tells me "no recording to play or no hard drive installed"
I have switched off the box and reinstalled hard drive with no effect and double checked the pins on the hard drive are all still straight.
Any ideas how I solve this so I can record?
Many thanks