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To turn on WordPress Multisite, you’ll need access to your website’s file system. You can do this by using an FTP connection, or by visiting File Manager in your web hosting control panel, or by installing File Manager in WordPress.
Once you have access to your file system, you’ll need to edit the wp-config.php file.
Look for the line that says: $table_prefix = ‘wp_’; (wp_ may be something different)
Add the line: define(‘WP_ALLOW_MULTISITE’, true); underneath the line above.
Save the changes to wp-config.php.
Go back to your WordPress dashboard, and you’ll need to deactivate your plugins (temporarily) to continue.
Once done, go to Tools > Network Setup.
The primary information in this section involves the decision to use sub-domains or sub-directories for your sites. This means each additional site in your network will be created as a new virtual sub-domain or sub-directory. Please choose whether you would like sites in your WordPress network to use sub-domains or sub-directories.
Check this radio button to utilise sub-domains for your sites. Examples of sub-domains are site1.example.com and site2.example.com. This features works by using wildcard subdomains. You must have this enabled in Apache, and you must also add a wildcard sub-domain to your DNS records. Some hosts will not support this, so you may need to ask your host before enabling this feature.
Check this radio button to utilise sub-directories for your sites. Examples of sub-directories are example.com/site1 and example.com/site2. Sub-directories work with mod_rewrite.
Note: If you wish to use fully qualified domains, you still need to pick a format to start with. Then after verifying they work, use the Domain mapping feature.
Fill in the rest of the information, and click Install.
On the next screen, you’ll need to copy some additional code to place below define(‘WP_ALLOW_MULTISITE’, true); in wp-config.php. and some code to place in the .htaccess file, replacing any existing WordPress code.
Once this has been done, you’ll need to login again, and then you can begin creating additional websites under Dashboard > My Sites > Network Admin > Sites.How to hire WordPress web developers