If you have installed oik-nivo-slider version 1.7 and oik version 1.17 AND are running your website on a version of PHP lower than 5.3.3, then you could get the following Warning message from the [nivo] shortcode.
Warning: json_encode() expects exactly 1 parameter, 2 given in /wp-content/plugins/oik/bobbfunc.inc on line
This post offers three solutions.
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