"Premature end of script headers" tells you that the script has failed to produce a correct HTTP header before exiting, possibly because there is either a runtime or a compile time error in the script.

There are several reasons why this might be so. Many are discussed on this site. Use this as an opportunity to explore here. Try typing "Premature" into the Search field, and look at some of the nodes that the search unearths. Many will provide useful info.