Support » Plugins » [Plugin: Wordbooker] Call to undefined function mb_http_output

  • Resolved theresa95


    Many thanks for the excellent plugin. It is a breeze to setup and use.

    I am receiving the following error in my logs, occurs when I visit the Settings page.

    ...Call to undefined function mb_http_output() in ...wp-content/plugins/wordbooker/wordbooker.php on line 1346

    I am guessing from what I have been reading that it is because of mbstring is not compiled into PHP (v5.3.2). Could you please confirm? I cannot touch PHP on this machine, so is this an important issue, do I need any workaround ( I can edit the file if necessary), or can it be just ignored? Thanks.

Viewing 4 replies - 1 through 4 (of 4 total)
  • mbstring should be there in anything above 4.0.6 and 5.0. So all I can assume is that whoever compiled your PHP install decided not to include it.

    Some PHP distributions (such as Fedora 9) allow you to add php modules using yum. You’d need to talk to your hosting provider.

    I use the multibyte strings to handle Facebook page names.

    So you need to comment out the following lines in wordbooker.php


    and change the following line in


    If that works then I’ll put some function checking in place so you don’t have to keep changing the code on each release.

    Ive posted a bug fix over on the Wordbooker Facebook page which should fix these problems.

    The problem is resolved but just FYI:

    Following your initial reply to my post I tried to login to the WP admin to do the required changes in wordbooker.php and wordbooker_cron.php. I was not able to login (just a blank page) and in server logs I was getting the errors:

    Cannot modify header information - headers already sent by (output started at .../public_html/wp-content/plugins/wordbooker/wordbooker.php:4627) in .../public_html/wp-includes/pluggable.php on line 868

    I had to remove Wordbooker directory to restore access. Following your subsequent post I have installed linked at the discussion thread “Theme problem” on Facebook and this has resolved the problem. No errors so far.

    Thanks again for an excellent plugin and sorry for messing your Sunday up.

    Live long and prosper.

    Thats very odd as wordbooker.php doesn’t contain 4627 line!

    But I’m glad its all working now

Viewing 4 replies - 1 through 4 (of 4 total)
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