desactivamos los plugin
en enlaces permanentes, enlace amigable permanentlink (Post name)

vamos al fichero wp-config.php

agregamos debajo de la linea 
/* Add any custom values between this line and the "stop editing" line. */



/*Multisitio*/
define('WP_ALLOW_MULTISITE', true);

salvamos


luego vamos a tools, network setup
damos clik en install

seleccionamos si lo queremos con sub-domain - sub-directories

y le damos al boton install

luego copiamos la informacion q nos muestra en wp-config.php y .htaccess

luego vamos al wordpress y hago click en Log In
una verz logueado ya me aparece el multisite





viendo lo de multiples dominios en el mismo wordpress mutliste
si sale error de cokkies agregar esto a
wp-config.php
define('COOKIE_DOMAIN', $_SERVER['HTTP_HOST'] );
 
----------------------------------------------------
para migrar de un sitio simple  a otro multisite

convierto a multisite al cual quiero unir los sitios
ebo ponerlo en modo de subdomain

1. para migrar de un sitio simple a un multisite
2. instalo el plugin prime mover en ambos sitios (en el sencillo y en el multisite)

3. voy al multisite y creo un sitio nuevo vacio
4. luego en el sencillo exporto y le digo que es para multisite y le pongo el ID del sitio que acabo de crear 
   en el multisite.
5. lo descargo
6. voy al sitio multisite y lo importo





Restore .htaccess to a single site setup

Next can be a tricky part. You'll want to remove the Multisite language from your .htaccess file if your hosting environment is Apache based (versus Nginx). A simple, default WordPress .htaccess file looks like this in most instances.

[gist id=”f864ac72304394f6dae4″]

However, your install could also have additional (legitimate) lines that have been added by plugins, especially if you have caching plugins enabled.

Therefore, keep an eye out for lines of code that are commented, which plugins should use to denote the beginning and end of their custom code. For instance, custom .htaccess lines from WP Super Cache are wrapped by lines that say # BEGIN supercache and # END supercache.
Drop Multisite database tables

Now your site should function normally in non-Multisite mode, but you still have some cleanup to do. The first step is to delete, or drop, Multisite specific database tables.

    wp_blogs
    wp_blog_versions
    wp_registration_log
    wp_signups
    wp_site
    wp_meta

If you are using the domain mapping plugin, you will also be able to drop the following two tables:

    domain_mapping
    domain_mapping_logins

You can do this from within phpMyAdmin if you have cPanel access with your host.



backup
wp_option
wp_blogs




