Title: Adding Multisite breaks WP
Last modified: August 21, 2016

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# Adding Multisite breaks WP

 *  [blogsterfiles](https://wordpress.org/support/users/blogsterfiles/)
 * (@blogsterfiles)
 * [12 years, 9 months ago](https://wordpress.org/support/topic/adding-multisite-breaks-wp/)
 * I suddenly have a new problem when installing multisite on shared hosts (networksolutions&
   mediatemple). I have multiple blogs with multisite (running with subolders not
   sub-domains) but suddenly whenever I add define(‘WP_ALLOW_MULTISITE’, true); 
   to wp-config.php, on fresh WP installs the site breaks.
 * Initially I get two error lines at the top of the control panel page that says“
   Warning: Cannot modify header information – headers already sent by~~”. If I 
   browse the site, the same message occurs but indicating various files and lines
   where the problem is originating. If I add the .htaccess and network settings
   to wp-config as I’ve done dozens of time before with no trouble, the site completely
   breaks.
 * Since this happened simultaneously on two different hosts and nothing has changed
   but the WP release, I’m thinking it must be a WP bug. Both hosts declare it is
   not a server problem and they want me to edit all of the dozens of WP files that
   are throwing errors but that just isn’t possible, nor do I believe would it solve
   the problem. If anyone else has run into this, or can point me in the right direction,
   I would appreciate it.

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Moderator [Ipstenu (Mika Epstein)](https://wordpress.org/support/users/ipstenu/)
 * (@ipstenu)
 * 🏳️‍🌈 Advisor and Activist
 * [12 years, 9 months ago](https://wordpress.org/support/topic/adding-multisite-breaks-wp/#post-3878842)
 * What’s the full error?
 * Sounds like you’re putting the define in a bad place.
 *  Thread Starter [blogsterfiles](https://wordpress.org/support/users/blogsterfiles/)
 * (@blogsterfiles)
 * [12 years, 9 months ago](https://wordpress.org/support/topic/adding-multisite-breaks-wp/#post-3878856)
 * Thank you [@mika](https://wordpress.org/support/users/mika/) …I have to run out
   at the moment and will have to re-create it when I return, but the error message
   starts the same and references various php pages and line. Searching the specific
   errors, all the forums indicate the errors are because of blank lines at the 
   end of the file or \<?php\ was not closed i.e. \?>\ … WordPress no longer uses
   the close tag on many pages and the blank trailing lines have never been a problem
   before.
 * The define is going above the line /* That’s all, stop editing! Happy blogging.*/,
   as I have always placed it. Bear in mind, I’ve done this dozens of times over
   the past few years and nothing has changed in the method used. I’ve literally
   spent hours on the phone with multiple people sending me links to their’s and
   WP codex instructions walking through it. Each time they have concluded it is
   a WP issue, not the install or their servers.
 * Thanks very much, will follow up with the error messages when I return.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Adding Multisite breaks WP’ is closed to new replies.

## Tags

 * [multisite](https://wordpress.org/support/topic-tag/multisite/)

 * In: [Networking WordPress](https://wordpress.org/support/forum/multisite/)
 * 2 replies
 * 2 participants
 * Last reply from: [blogsterfiles](https://wordpress.org/support/users/blogsterfiles/)
 * Last activity: [12 years, 9 months ago](https://wordpress.org/support/topic/adding-multisite-breaks-wp/#post-3878856)
 * Status: not resolved

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