Broken cubase 6 install disk - what to do?

Year 2012 I bought Cubase 6 Artist. Last week i had to re-install OSX and after that, Cubase.
When i tried to install Cubase, i saw an error message. I think that the install disk is damaged some how.
Is there any way i can order a new install disk or download .iso image or do i really have to buy Cu again because of a broken install disk?

I have the usb-dongle and maybe i can find the receipt from the shop i bought Cu from but finding it will take some time…