Search feature returns Fatal error

I am having a problem with the search function of my elgg site, Only logged on members can make use of the function. If a non logged on visitor trys to search for something they recieve a fatal error message. Any ideas how I can go about fixing this or at the very least hide the search box from non logged in members.

Beginning Developers

Beginning Developers

This space is for newcomers, who wish to build a new plugin or to customize an existing one to their liking