DSS Lite comes only in 32bit mode only the paid version can you get 64bit mode and if you upgrade to the paid version and enter the product then you have the option to use the 64bit mode. Keep in mind that this is a free version with limited options and you dont have to use it as you can test the Trial version that has the 64bit mode and you can use it in your lab for 60 days and you have all the options like the paid version. Keep in mind that we wanted to offer a free version for many that dont want to pay for just simple iSCSI or NAS functions.