Suppose we have a plane to install WordPress multisite, and sudden due to any reason we have to stop installing or facing some issue, and again we are trying to install then we face a Warning: An existing WordPress network was detected, so in this case follow these techniques and install multisite on your WordPress blog.
This issue can come for the following reason:
define('DOMAIN_CURRENT_SITE', 'Your website URLs);
Note: Always take a backup of old wp-config file while you are migrating for a multisite WordPress website.
In some case WordPress again allows you to install WordPress multisite, if you are facing same issue then truncate following table from the database, because ita already been install whenever we had tried to install WordPress multisite.
Drop the following table from the database:
After doing all these steps, now log out and log in again and ready to install WordPress multisite for your blog.