Started receiving errors a few days ago

I'm not sure this is a dashboard error but I noticed I started getting these a few days ago. They're identical and come once or twice a day. Any ideas how to correct?

"[26-Jan-2016 15:44:31 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/i1pvin0g3nic/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539"

Thanks,
Larry