Could not find custom/install/install_hooks.php


during the install of suiteCRM and directlyt after filling information about database and suiteCRM user credetiels (third page) i got an error HTTP 500 in my borwser. when i checked the install.logs i find this error in the last line : installerHook: Could not find custom/install/

1-Is there any relation with HTTP 500 error and this installerHook error .
2-How we can proceed to solve this issue ?

Thank you