Cisco switch SG500x (new)- I'm unable to make and save changes using the console session...

hi guys,

I've got a Cisco SG500x-24 that has been sitting there in a box. I'm about to put it into production, so I'm trying to configure it. I've upgraded the firmware to 1.3.7.18.

I'm connecting using the putty application and I merely want to give this thing an IP address and configure VLAN's.
First of all, I can't enter the 'enable' mode as i get 'unrecognised command'. So instead I go in and type 'conf t'. That goes through and then when I add the VLAN1 with an IP address and then type 'copy running-configuration startup-configuration' again I get 'unrecognised command'. I'm confused as to what is causing this? Is the firmware not new enough?

Thanks for helping out
Yashy