radio wont switch on l322 rangerover 4.2s

Hi all,
The battery went flat on my 2005 range rover 4.2s, new battery fitted .following this the radio or nav or cd will not switch on. The orange light on the on/off switch flashes and the touch screen shows the landrover logo and is lit up , but it will not come on no matter what you press !
Any ideas , is there a reset procedure ? Thanks Phil

Try disconnecting that battery again for about five minutes - then see if it resets properly.

Just make sure that the battery is fully charged and when you make the connection that it's a good one with no fiddling about.