Cannot get AutoCAD to install on my Mac HELP!

[chri_see]

Hiya, I've got a 1 year old Macbook Pro with MacOS Extended (Journaled), which I understand is supposed to be compatible. 

I downloaded both the 2012 and 2011 AutoCADs and after downloading for about half an hour once I try and open the downloads to install the following warning message comes up:

Completely new to AutoCAD (I'm a student) and not particularly a whizz with my mac, any help would be much appreciated! 

Have also emailed the Autodesk help service so awaiting advice from them too! 

[DarrenP]

you have to have this OS

Mac OS® X v10.6.4 or later

[chri_see]

I have version 10.6.8! 

[p.pietrucha]

And what to do if I have Mac Book Pro 5.2 and version of Mac OS X 10.5.8 -  I downloaded Auto Cad 2012 trial but it requires the version of Mac OS X 10..6.4 or later, I' m beginner user of Mac, should  I update the softwer or ? Have no idea what to do and would appreciate any help, thanks

[DarrenP]

you need to upgrade your OS to meet system requirements

[chri_see]

Sorry, should have updated this sooner! I managed to fix it, very simple actually.

I was downloading the software via Google Chrome, but it only worked when I tried downloading it via Safari instead, not really sure why that worked and Chrome didn't, but thanks for everyone's help!