Fatal error: Call to undefined function mb_substr()
In this article we will explain you how to fix this error.If you get this error on your website it means that mbstring is not enabled or installed on your web hosting server.
If you are using multibyte character encoding in your code, you will get this error when the mb_substr() function is called.
To fix this error you need to install mbstring php module.If you are using VPS or dedicated server this can be done easily.if you don’t have a root access to your server you need to contact your hosting provider and ask them to enable this mbstring PHP extension for you.
How to fix this error?
To fix this error we may use 2 ways:
1-We can do it through php.ini file.
2-We may use EasyApache to recompile PHP with mbstring module.
To fix this error through php.ini file,Go to your php.ini file and search for extensions. Into the list of extensions if you find mbstring then the extensions would be installed on server.If the line is commented out then it is not enabled to enable it remove the comment and restart the Apache.
Secondly we may use EasyApache, To recompile Apache First of all Login to your WHM as root.
Search for the EasyApache in the search box and click on it.
Click Start customizing based on profile.
Next, you will be persuaded to choose your Apache version. Just keep the already selected option. We will not need to create any changes to Apache.
After the Apache, you will then choose your PHP version. You will want to keep this the same as what is already chosen as well, since modifying your PHP version can possibly crack your current websites if they need a greater or lower version of PHP. Just simply select the Next Phase to check out the next web page.
After choosing your PHP version, you will see the Short options list.Go to the end of the page and simply click on Exhaustive Options List.
Now that you are on the Exhaustive Options List, you will see Mbstring under the PHP area. To allow mbstring, simply select the check box to the left of it. Once it is chosen, search to the end and simply just click Save and Build.
Once it has completed your problem should no longer persist.