If you get the error “Call to undefined function wp_get_current_user()” when running Multisite on WordPress, there’s am easy fix that may help you.

Step by step

  1. Remove the line “define(‘MULTISITE’, true);” from your wp-config.php in order to reset your site to a normal WordPress installation.
  2. Deactivate ALL your Plugins.
  3. Reenter the line define(‘MULTISITE’, true); to wp-config.php.
  4. Try entering the Network Admin Dashboard via /wp-admin/network/

The error is most likely being caused by a plugin that interferes with the wp_get_current_user() function.

Followup

If you are still having trouble, here are a few links that might help you


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