Title: Warning: array_key_exists(): Last modified: August 20, 2016 --- # Warning: array_key_exists(): * Resolved [knutsson](https://wordpress.org/support/users/knutsson/) * (@knutsson) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/) * I get this message when I activate the plugin, in the header. * Warning: array_key_exists(): The second argument should be either an array or an object in wp-content/plugins/nextgen-facebook/nextgen-facebook.php on line 277 * Whats wrong? * [http://wordpress.org/extend/plugins/nextgen-facebook/](http://wordpress.org/extend/plugins/nextgen-facebook/) Viewing 15 replies - 1 through 15 (of 18 total) 1 [2](https://wordpress.org/support/topic/warning-array_key_exists-5/page/2/?output_format=md) [→](https://wordpress.org/support/topic/warning-array_key_exists-5/page/2/?output_format=md) * [theshae](https://wordpress.org/support/users/theshae/) * (@theshae) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348925) * I’m getting the same error on a fresh install running 2012 theme * [RMJ](https://wordpress.org/support/users/rmj/) * (@rmj) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348939) * Possibly related error but I updated my plugin (from dev version) to public 2.4 and I’m getting this error: * `0 is a protected WP option and may not be modified` * The plugin won’t activate anymore. I even tried to delete it and re-install but same thing happens. Instlalling older version works just fine. * (I did not see the array error anywhere even turned on WP debug info. Just some notices of undefined variables related to this plugin) * Plugin Author [JS Morisset](https://wordpress.org/support/users/jsmoriss/) * (@jsmoriss) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348940) * Thank you for letting me know. I’m just finishing up a major update and will be releasing v3.0 this afternoon. * Line 277 in v2.4 refers to a section that checks to see if all the options exist, and if one doesn’t (in case of an update, for example), it creates it with a default value. * ``` foreach ( $this->default_options as $opt => $def ) if ( ! array_key_exists( $opt, $opts ) ) $opts[$opt] = $def; ``` * This section of code, like pretty much all the rest of the code, has been revised. That specific line hasn’t changed much, except that I’ve added a check to make sure the associative key has a value. * ``` foreach ( $this->default_options as $def_key => $def_val ) if ( $def_key && ! array_key_exists( $def_key, $opts ) ) $opts[$def_key] = $def_val; ``` * If you wouldn’t mind, could you give the DEV version a spin? * [http://downloads.wordpress.org/plugin/nextgen-facebook.zip](http://downloads.wordpress.org/plugin/nextgen-facebook.zip) * It’ll show v2.9 for now, until I release the final code as v3.0 this afternoon. * Thanks, * js. * Thread Starter [knutsson](https://wordpress.org/support/users/knutsson/) * (@knutsson) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348945) * The Warning has gone away, but in my theme I cant get the meta tags to show. But in the standard Twentyelven it works fine. * you can check my site at kmagazine.se * Plugin Author [JS Morisset](https://wordpress.org/support/users/jsmoriss/) * (@jsmoriss) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348950) * Hm. Ok… * Would you mind turning on debugging? It’s an option at the bottom of the NGFB settings page. * Thanks, * js. * Thread Starter [knutsson](https://wordpress.org/support/users/knutsson/) * (@knutsson) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348956) * I have done it, but you have to check at [http://www.eypaco.se](http://www.eypaco.se) beacuse the other page I dont want to mess with so much:) * Plugin Author [JS Morisset](https://wordpress.org/support/users/jsmoriss/) * (@jsmoriss) * [13 years, 4 months ago](https://wordpress.org/support/topic/warning-array_key_exists-5/#post-3348958) * BTW, if you take a look at your HTML source, there are a few issues… * – You should remove those blank lines before the !DOCTYPE. * – There’s a `
` in the head section — that’s a no-no. * – The first anchor `