Errors (Notices) on Server from WPMU plugins.

How do I correct these?

Notice: Undefined index: key in /home/tawesome/public_html/wp-content/mu-plugins/post-indexer.php on line 40

Notice: Undefined index: domain-default in /home/tawesome/public_html/wp-content/mu-plugins/site-wide-text-change.php on line 366

Notice: Undefined index: domain-default in /home/tawesome/public_html/wp-content/mu-plugins/site-wide-text-change.php on line 367

Notice: Undefined index: domain-wp-pagenavi in /home/tawesome/public_html/wp-content/mu-plugins/site-wide-text-change.php on line 366

Notice: Undefined index: domain-wp-pagenavi in /home/tawesome/public_html/wp-content/mu-plugins/site-wide-text-change.php on line 367

Notice: Undefined offset: 1 in /home/tawesome/public_html/wp-content/mu-plugins/update-notifications.php on line 62

Notice: Undefined offset: 1 in /home/tawesome/public_html/wp-content/mu-plugins/update-notifications.php on line 55