How to Enable Multisite in WordPress

This video screencast is a quick tutorial for how to set up WordPress 3.0 in multisite mode. The WordPress codex has written instructions if you want to use those as well.


Update the wp-config.php file

You will need to add this line of code to your wp-config.php to make the multisite function accessible:

define('WP_ALLOW_MULTISITE', true);


WordPress codex documentation for using multisite:

How to map top level domains in multisite:

About Devin

I am a developer based in Austin, Texas. I run a little theme shop called DevPress and help manage a WooCommerce shop with Universal Yums. Find me on twitter @devinsays.

114 Responses

  1. jack

    I tried to install follow the video. When visit the new created mysite, shows error 404 page.

    The error mesage is
    PHP Warning: chmod() [function.chmod]: No such file or directory in /home/abc/public_html/prepare_removal.php on line 110

    How to fix this?


  2. My host will not allow me to put a .htaccess file. Does this mean I cannot use the multi-site option?
    I am now running multiple installs of WP 2.9.2 and I would love to get rid of the duplication of the WP code for each of my blogs.

  3. I upgraded from 2.92 to 3.0 and just tried to implement multisite but did not get a network link in the tools menu as advertized.
    I double checked that
    define(‘WP_ALLOW_MULTISITE’, true);
    is in the wp-config.php

    Any suggestions?

  4. @County
    Some people say it is
    define(‘WP_ALLOW_MULTISITE’, true);
    others say it is
    define(‘WP_ENABLE_MULTISITE’, true);

    I did both and that got me the multisite links…

    Unfortunately I am havig trouble combining it with WPML now, but that is another story…

  5. I cannot see the tutorial video, I look at a Mac with Firefox and/or Safari. Both nothing but a white square. Its a pitty because I was curious about the tutorial.

  6. Jelskedei

    Thanks, After a while I got it on both browsers. I never had this before, such a long time before the video started, it was maybe busy or it was too hot (in Holland). But anyway, thanks a lot for your support and help.

  7. Sri

    After enabling multisite, would it let me use the same username and password for all my existing users among all the sites ?


  8. marco

    This is all fine and dandy for those that have never used WP and are starting fresh, but what about those that have been using a single WP installation and want to migrate to Mulstisite>?

      1. Max

        And be careful if you have had the install for a long time (permalink problems) – codex does not recommend you do a switch if your site has been running for a long time.

        Check — specifically the bit titled “WordPress Settings Requirements”, where they say you cannot choose Sub-Directory install if your site has been running for more than a month (although they claim to be fixing this in later versions).

  9. Rob

    I have successfully enabled multisite, installed MU Domain Mapping and added a second site mapped to a new domain. Everything is working fine, but I have a question about privacy:

    My original site is my business site and the new site is entirely personal, and supposed to be anonymous. However, when you watch the browser’s (firefox) path to the new site while it loads (in the address bar at the bottom), you can see it hit the original site address just before the plugin maps it to the new site domain. Occasionally when the servers are busy you can see “waiting for” before it gets mapped.

    Is there any way to keep visitors to the new site from ever seeing the address of the original site?

    1. Max

      MU Domain Mapping works with a 301 Redirect. If you are keen eyed and on a low connection you will see that as the server sends the redirect header, and then the browser requests the new URL.

      There is really not much you can do to prevent that… On a fast connection and server it would be near instantaneous (provided the new domain name is already in the DNS cache).

  10. I installed this site as a multisite on my domain. I am using the Thesis theme for all my site. On the multisite install, I can’t find the install files for my new sub sites. I need to change for the pictures in that rotator folder, which is inside the wp-content folder. I only have the master install files, not the install files for my sub sites. The site is working correctly, so the pictures have to be somewhere. I checked using my ftp client and also through the file manager in cpanel. Any thoughts?

  11. Our existing site runs 3.0 and does not have the network enabled. I followed the steps from the WordPress site to enable the network. Once I activate Network and add the code supplied by WordPress to wp-config and .htaccess and then logout, it says it doesn’t have a database connection. I commented out the new code from the wpconfig and then it works again but not as a network site. Is there something else that needs to be done. We have 2 installs on the site(one is for the main site and the other is press releases) and would prefer to have one multi-user site that we basically clone to our other translated regions.

  12. I’m about to pull my hair out. The procedure described in this post and in the video works fine for me on my hostgator server. As soon as I’m finished, I can immediately access the newly created sub-domain. However, on another one of my servers (not hostgator), everything seems to work fine during the install, but when I go to try to visit the newly created site, nothing is there!

    I’m certain the problem has to be something on the server. My hosting company is willing to help me figure this out, but they don’t know what’s wrong anymore than I do, so if I’m going to get this to work on their servers, I have to be able to tell them what to fix!

    What do I do? Does anyone have any ideas? Anyone?

    1. Max

      Probably is your hosting company. Many of them do not like you running Multi-Site on Shared hosting — quite simply as it taxes their machines — and you can run way more domains than they may allow using MU Domain Mapper.

      Hostgator are awesome and pretty much allow you to do anything, but will throttle you if you start to overload the web-server.

  13. nice plugin for the community, i’ll try to write an automation for domain mapping (SUNRISE) too, maybe will complete this plugin.

    ps. what font do you use in this theme because text in posts looks ugly in linux? :P Try not to use “Lucida Grande”,Calibri and other new microsoft fonts, they look ugly on other operating systems (mobile phones for example)

  14. Thank you so much for this posts. It helped quite a bit in getting the multiple site created.
    Unfortunately, the site I am supporting uses a custom-made theme that doesn’t seem to work on the secondary site I created. It is network enabled but the custom header and menu do not appear on the second site (I have a sub-directory install). oy vey!!!

  15. I followed your tutorial, but when trying to access the dashboard of my newly added site, I got the 404 (Page Not Found) Error page. Can you help me fix that?


  16. after the network setup i have used the copy the code of httaccess and wp-config and pasted as follwed by instruction and uploaded in server but mu is not working i am not getting the super admin and network adminstrator

  17. marisa

    do you have to have the site name registered first? And I’m assuming you do NOT want to have wordpress installed on that site? I keep getting error messages.

  18. hillman

    Hi Devin,

    Thanks for your video. I followed the multi-site instruction and created my wordpress site at Then I tried to create site1 as a test. It said the new site1 is addred but when I view the site1 failed with an error:
    The requested URL /site1/wp-admin/ was not found on this server.

    It seems that the site1 did not create or somehow the path for the multisite is not configurated properly. Any hints or ideas on how to fix this problem. Thanks…. Hillman

  19. I read other instructions and they say lots of things. Is this all we need to do – adding a single line of code? And then setting up subdomains in the wp dashboard?

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