admin/environment/php extension/iconv

From MoodleDocs

Windows

To enable iconv in Windows package installations of Moodle:

  1. Open the php.ini file found in the moodle/apache/bin folder
  2. Find the line: ;extension=php_iconv.dll
  3. Remove the ; at the beginning of the line
  4. Restart apache for the change to take effect.
   Note: The iconv module is now part of PHP as of PHP version 5 so 
   the php_iconv.dll file is not needed anymore. It is no longer 
   included as an extension in the php.ini-recommended file in the PHP 
   Windows binaries package and you do not need to enable the extension 
   in your php.ini file. In other words, you do not have to enable the 
   extension=php_iconv.dll line in your php.ini file.
   See http://www.php.net/manual/en/iconv.installation.php for details.

Ubuntu Linux

If you installed your PHP using the Ubuntu repositories (apt-get), then you should have iconv installed by default. If you compiled PHP from source then you will need to recompile with iconv support.

Other OS

This page needs to be enhanced by adding corresponding instructions for other kinds of Moodle installations.