I am getting the exact same error…Here’s the other PHP errors I’m getting with this plugin. What’s so strange is I have this plugin working flawlessly on another Multisite install and the current install is on a fresh install of 3.1.1 that I’m setting up for development. Running latest version of plugin and wordpress.
PHP Notice: Undefined variable: wp_version in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 677, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/plugins.php?deactivate=true&plugin_status=all&paged=1&s=
PHP Notice: Undefined index: action in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 144, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/settings.php
PHP Notice: Undefined index: permanent_redirect in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 303, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/settings.php?page=dm_admin_page
PHP Notice: Undefined index: dm_no_primary_domain in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 306, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/settings.php?page=dm_admin_page
PHP Notice: Undefined index: 1 in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 825, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/settings.php?updated=true
PHP Notice: Undefined index: 2 in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 825, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/settings.php?updated=true
PHP Notice: Undefined index: 3 in /var/www/itscblogtestsite/html/wp-content/plugins/wordpress-mu-domain-mapping/domain_mapping.php on line 825, referer: https://itscblogtestsite.tamu.edu/wp-admin/network/settings.php?updated=true
Thanks
– Trey