Hi Eileen,
Please go to the Software Downloads page.
Click on the “Change Software Preferences” link, select RTTOV, and then scroll down and agree to the Licence by clicking “Update Software Preferences”.
This should take you back to the Software Downloads page. If you cannot see a link to download RTTOV, then please refresh the page (e.g. Ctrl-F5 in Firefox).
If this still does not work please raise a ticket through the help desk.
Best wishes,
James