Support » Installing WordPress » Warning: Cannot modify header information – header

  • page_

    (@page_)


    Ok, just downloaded the latest stable version and am trying to install it on a linux server. PHP Version 4.3.6 is running as CGI.
    Got through all the install steps ok, and I’m now at the login screen. When I try to login, I’m getting the following errors…
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 124
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 128
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 131
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 133
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 134
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 135
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 136
    Warning: Cannot modify header information – headers already sent by (output started at /path/to/wp/wp-login.php:3) in /path/to/wp/wp-login.php on line 156
    The only other solutions I’ve found for this in the forums is to delete the last blank line on vars.php . I’ve since gone through all the files that are called from wp-login.php and sub-required files to delete any last blank lines of the file. I’ve done a lot of tweaking and several blank installs but all to no avail.
    Love to hear your suggestions to get this running…

Viewing 12 replies - 1 through 12 (of 12 total)
  • page_

    (@page_)

    ok got it sorted. I had to go through all the word press files that set cookies and/or send out header information and wrap them in ob_start() -> ob_end_flush();
    It’s going to make upgrading in the future a pain, so could the WP team look at wrapping all header information in these functions?

    Nick Momrik

    (@mtdewvirus)

    The most common problem that gives the “headers already sent” message is an extra blank line before the <?php or after the ?> in the config file or the hacks file.

    foolfillment

    (@foolfillment)

    I’m getting similar errors, I’ve checked my wp-config file for that problem but it wasn’t the cause, any ideas?
    my error goes along the lines of :

    Warning: Cannot modify header information – headers already sent by (output started at /usr/local/psa/home/vhosts/mydomain.co.uk/httpdocs/refer/refer.php:164) in /usr/local/psa/home/vhosts/mydomain.co.uk/httpdocs/wp/wp-login.php on line 109

    The reason you’re getting this error is because you’re using a call to a header function after you’ve printed (echoed) text to the html.
    When using a header function, it is a php requirement to utilize it before any html is displayed.
    To avoid this problem, what I usually do is, rather than echo lines of html, I store the html in a variable. Then, I do the test if(condition) then print html else header.
    This way, you avoid printing out html, and the header function will be valid.

    thanks to this site!

    I got the same error and it was fixed by deleting the extra spaces before <?Php and after the ?>

    Hi guys, I have the same problem. Did you ever get this fixed?
    I run WP 1.5

    Thank you,

    Steve
    http://www.GeekTavern.com

    Mark (podz)

    (@podz)

    Support Maven

    Thanks, MtDewVirus, for your suggestion about the blank lines… I had a bunch of the “Warning: Cannot modify header information blah-blah-blah warnings in my WP admin screens and deleting the extra lines in the file it referenced (at the end, no less!) totally solved my problem!

    Thanks again!

    MtDewVirus: I’m getting this error (which began after activating a plugin–why would activating a plugin that already had been deactivated & then reactivated cause this) & I have no extra lines at the beginning or end of the file. To be safe, I deleted every blank line in the entire file, then saved.

    Still getting errors.

    UPDATE: I examined one of the files causing the error & it was for a plugin that not only wasn’t active, but I was sure I deleted it. ONce I deleted that file, the error stopped. BTW, the file causing the conflict had no blank lines or spaces in it either at the beginning or end.

    Moderator James Huff

    (@macmanx)

    Volunteer Moderator 🚀

    Please quote the error here.

    UPDATE: Nevermind

    I also got the same error,
    Thanks to MtDewVirus… now it is working…

    Street Racing Videos

Viewing 12 replies - 1 through 12 (of 12 total)
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