Weird error in logs when activating script

I run this on 7 sites with no problem. Put it on another and can’t activate. I get a 500 error.

Error logs show

gives me a 500 error. So, I check error logs

[Fri Nov 29 20:48:53 2013] [error] [client *******7] PHP Fatal error: require() [function.require]: Failed opening required ‘./wp-blog-header.php’ (include_path=’.:/opt/php5214/lib/php’) in /mnt/glusterfs/apache/hosting-dir/****/user_dir/domain.com/index.php on line 17

[Fri Nov 29 20:50:01 2013] [error] [client ******17] terminate called after throwing an instance of ‘, referer: http://www.domain.com/wp/wp-admin/plugins.php?activate=true&plugin_status=all&paged=1&s=

[Fri Nov 29 20:50:01 2013] [error] [client *****.17] suPHP::LookupException, referer: http://www.domain.com/wp/wp-admin/plugins.php?activate=true&plugin_status=all&paged=1&s=

First error appears to be chmod but what should that file be set at?

Second/third are this plugin failing to activate. Why?

http://wordpress.org/plugins/register-ip-multisite/