As a reseller I can tell you the free version is on the grisoft home page in the upper right corner under the orange RENEW LICENSE. You can download it again for free when it expires in 30days. The advantage to buying the software is it is a 2 year license and most of all tech support is free. Please be aware that the free trial version will only download updates and the latest definitions after it has done the registered users. In other words free trial users wait till registered users finish downloads.