I checked the same and found that when you go for the download of the triaware for Symantec Protection for SharePoint Servers from the Web Site mentioned, you need to register and after the registration you will be asked to fill a survey.
Once you are done wiht the survey, there is a email sent to your email account which has a 30 Day Trialware License.
The attachment looks like 18245771.slf.zip. You will have to extract it, as it is a zip file.