"Security key was not detected or unavailable license. Please contact technical support."
There could be two reasons:
1) This is a new installation and the license has not been onfigured yet.
2) All the available licenses are in use.
Software Download Instriuctions
http://communities.bentley.com/products/licensing/w/licensing__wiki/3135.aspx
http://communities.bentley.com/products/licensing/w/licensing__wiki/2781.aspx
http://communities.bentley.com/products/structural/structural_analysis___design/w/structural_analysis_and_design__wiki/3415.selectsupport-technotes-and-faqs.aspx