Hi,
I seem to be having this problem after upgrading from D6 to D7 .. when cron runs crashes our server.
Location http:///?/home/public_html/cron.php
I agree the above location is incorrect, so disabled the internal cron (admin/config/system/cron) in D7 to 'run cron never' and setup a cron via cpanel with the external cron path key which runs without every hour problem.
Yet every 8 hours or so another cron runs, don't know where it comes from with the following errors:
Notice: Undefined index: REQUEST_METHOD in _block_render_blocks() (line 830 of /home/public_html/modules/block/block.module).
Notice: Undefined index: REQUEST_METHOD in module_implements_write_cache() (line 770 of /home/public_html/includes/module.inc).
Notice: Undefined index: SCRIPT_NAME in request_uri() (line 1591 of /home/public_html/includes/bootstrap.inc).
Notice: ob_flush() [ref.outcontrol]: failed to flush buffer. No buffer to flush. in drupal_page_footer() (line 2571 of /home/public_html/includes/common.inc).
Notice: Undefined index: REQUEST_METHOD in SchemaCache->__construct() (line 2815 of /home/public_html/includes/bootstrap.inc).
Cron could not run because an invalid key was used.
Notice: Undefined index: REMOTE_ADDR in ip_address() (line 2741 of /home/public_html/includes/bootstrap.inc).