Garmin c510

Good morning to you all mainly the techno people, I have a garmin c510 street pilot and I have had it for a number of years. It was a great asset while i was driving trucks around Perth. I now have a problem and it is this. On the weekend I brought an updated version of the maps of Australia, from Garmin at great cost to management, and with out consulting the minister of finance ,I know bad mistake, and now I find that I can't down load it to the machine, I keep getting the message machine has not got the memory capacity to handle the down load with out having a card for it. I went to office works and brought a 32gb card and I still get the same answer , the question is this,is my machine to old to handle the down load and do I need to upgrade the machine or am I doing some thing wrong. I think I have followed the instructions to the letter for the down load but I am still getting the same answer. HELP REQUIRED PLEASE. Thank you.
Broodie H3