Hi there, sorry for delay.
Which version of PHP do you have?
This requires 4.0.6 or above
This will tell you: https://wordpress.org/plugins/display-php-version/
If you do have that version or above, it’s likely the mb_strings module is missing from PHP.
From another plugin author: “This error could mean that you don’t have the mb_string module turned on within your server. Try talking to whoever manages your server about it.” (http://wordpress.org/support/topic/fatal-error-undefined-function-mb_convert_encoding?replies=2)
I’ll see if we can find alternative to this function which can be troublesome.
We have PHP version 5.x on all of our servers.
Please talk with your server admin about enabling mb_string as mentioned in this thread. This will solve the issue.
I’ll look at removing that dependency in a future version.
