Title: Fatal error
Last modified: August 20, 2016

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# Fatal error

 *  Resolved [callummccormick](https://wordpress.org/support/users/callummccormick/)
 * (@callummccormick)
 * [13 years, 2 months ago](https://wordpress.org/support/topic/fatal-error-702/)
 * Hi Guys,
 * I thought I’d cracked all my problems recently (!) but tonight, I pressed the
   Publish button and I get this:
 * Fatal error: Call to undefined function mb_encode_mimeheader() in /home/dreamers/
   public_html/cms/wp-content/plugins/subscribe2/classes/class-s2-core.php on line
   354
 * I can’t think what I’ve changed. Maybe a plugin or two, but nothing drastic..
 * Best action to resolve?
 * Cheers,
 * Callum.
 * [http://wordpress.org/extend/plugins/subscribe2/](http://wordpress.org/extend/plugins/subscribe2/)

Viewing 3 replies - 1 through 3 (of 3 total)

 *  [Matt Robinson](https://wordpress.org/support/users/mattyrob/)
 * (@mattyrob)
 * [13 years, 2 months ago](https://wordpress.org/support/topic/fatal-error-702/#post-3612268)
 * [@callum](https://wordpress.org/support/users/callum/),
 * This is a known issue. It is discussed with a fix here:
 * [http://wordpress.org/support/topic/subscribe2-8?replies=6](http://wordpress.org/support/topic/subscribe2-8?replies=6)
 *  Thread Starter [callummccormick](https://wordpress.org/support/users/callummccormick/)
 * (@callummccormick)
 * [13 years, 2 months ago](https://wordpress.org/support/topic/fatal-error-702/#post-3612332)
 * Hiya Matty,
 * Happy to add / change the code as suggested in your known-issue post or do a 
   roll-back. Can you explain the search and replace procedure for this code snippet?
 * Alternatively, I could roll-back, but I don’t have the previous version.
 * Your advice, as always, a pleasure to receive 🙂
 * Callum.
 *  [Matt Robinson](https://wordpress.org/support/users/mattyrob/)
 * (@mattyrob)
 * [13 years, 2 months ago](https://wordpress.org/support/topic/fatal-error-702/#post-3612344)
 * [@callum](https://wordpress.org/support/users/callum/),
 * To update the code, open it in an editor then use a search or find function to
   locate the affected line of code. Finally, replace to affected code with the 
   new code. If you use the WordPress plugin editor make sure to deactivate the 
   plugin first just in case you introduce a syntax error as this will take your
   entire site down.
 * You can always revert to any previous version by accessing them here:
    [http://wordpress.org/extend/plugins/subscribe2/developers/](http://wordpress.org/extend/plugins/subscribe2/developers/)

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Fatal error’ is closed to new replies.

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 * 3 replies
 * 2 participants
 * Last reply from: [Matt Robinson](https://wordpress.org/support/users/mattyrob/)
 * Last activity: [13 years, 2 months ago](https://wordpress.org/support/topic/fatal-error-702/#post-3612344)
 * Status: resolved