Error HTTP 500 new OJS installation

im trying to make a new OJS installation, but i receive a blanck page with 500 error.

this message

Fatal error: Class Application contains 1 abstract method and must therefore be declared abstract or implement the remaining methods (iPKPApplicationInfoProvider::getSubmissionSearchIndex) in /home/codexhrp/public_html/ojs/classes/core/ on line 31

some idea?