admin/environment/php extension/mbstring

If you want to have mbstring work on a LAMP server with yum (Fedora, Redhat, Centos) or apt-get (Ubuntu, Debian) then do this

1) As root from the CLI yum install php-mbstring or in the apt-get case apt-get install php-mbstring

For php7 on Centos do: "yum install php70-mbstring"

Then restart Apache

either /etc/init.d/httpd restart or possibly /etc/init.d/apache2 restart

Then check your server Environment again and the whinge from Moodle should have gone away and rewarded you with a nice tick or such-like.

To enable the mbstring library in Windows package installations of Moodle:

Open the php.ini file found in the moodle/apache/bin folder or Windows folder
Find the line: ;extension=php_mbstring.dll
Remove the ; at the beginning of the line
Restart apache if necessary

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

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