I can see I get this error all the time in my error log.

Hi,

I can see I get this error all the time in my error log.

[01-Feb-2016 09:33:56 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[01-Feb-2016 21:21:02 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[02-Feb-2016 09:55:06 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[02-Feb-2016 21:20:27 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[03-Feb-2016 09:35:43 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[03-Feb-2016 21:59:44 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[04-Feb-2016 09:27:26 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[04-Feb-2016 21:34:23 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539
[05-Feb-2016 09:21:20 UTC] PHP Fatal error: Call to undefined function is_plugin_active_for_network() in /home/problocksterco/public_html/wp-content/plugins/wpmudev-updates/includes/class-wpmudev-dashboard-api.php on line 539

What is this?