New Page error 2.7

when I try to create a new page it gives me this error:

Warning: main(edit-page-form.php): failed to open stream: No such file or directory in /home/content/s/i/a/sianta06/html/co/saltsprings4h/siteprotect/wp-admin/page-new.php on line 26

Warning: main(): Failed opening ‘edit-page-form.php’ for inclusion (include_path=’.:/usr/local/lib/php’) in /home/content/s/i/a/sianta06/html/co/saltsprings4h/siteprotect/wp-admin/page-new.php on line 26

I tried serching for edit page form.php in the wordpress directory but i couldn’t find it.