After updating a 3.4.2 network install to 3.5, I receive

Fatal error: Call to undefined function nocache_headers() in /wp-admin/admin.php on line 32

This happens in Chrome, and in Firefox (when I am not logged into admin).

I have downloaded a 3.5 zip, and uploaded and overwritten /wp-admin, but the issue remains.

I have also renamed plugins to plugins2, but the issue remains.

closed as too localized by fuxia Dec 18 '12 at 13:11

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There were wp files in the web root which had file size of 0 bytes.

Uploading proper copies from the zip file resolved the problem.

The same cause of the problem has occurred to me quite a few times in the past, but I had forgotten it.

  • 1
    please describe more about this wp file that i cant found that in zip file – saber tabatabaee yazdi Jan 21 '13 at 9:03
  • 1
    They were just wp-* files found in the web root. – Steve Jan 22 '13 at 4:22
  • Fatal error: Call to undefined function is_multisite() in /home/baseline/public_html/wp-includes/default-constants.php on line 20 – saber tabatabaee yazdi Jan 22 '13 at 5:06

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