Php 5.1.x is unsupport in 6.5.1 because too old. As the same as 6.5.0, still support 5.2.x.
Try this custom:
1. copy '/home/phpini/tpl/htaccess.tpl' to ''/home/phpini/tpl/custom.htaccess.tpl'
2. modified custom file:
from:
### begin content - please not remove this line
to:
<?php
if ($domain === 'domain.com') {
return;
}
?>
### begin content - please not remove this line
where change 'domain.com' to your domain
3. run 'sh /script/fixphp; sh /script/fixweb; sh /script/restart-web';