[Plugin: Revision Control] Complains that WP_POST_REVISIONS is defined and cannot operate

Perhaps WP_POST_REVISIONS has been defined by your theme. Try looking in the theme’s functions.php file. The plugin has worked without any problems for me on multiple WP 3.x sites.

Unfortunately, I don’t seem to have a functions.php file in my theme.

Really? That’s not impossible but it’s pretty unusual. Have you looked through all of your other theme files?

Nah, I need to get home where I have shell access in order to run a grep. I’ll do that later.

I have the same issue now. Did you resolve yours and if so, how?

Thanks.

Found the issue and fixed it. For anybody else that encounters a similar issue and does not want to (or cannot afford to) take the site offline and disable all the plugins to test, here’s what I did:

1. After a fair amount of research, figured out that the attribute that determines whether the “Revisions” Meta Box shows in Screen Options is WP_POST_REVISIONS. This is set to “True” by default but, can be overridden in wp_config.php. More info here.

2. Downloaded via FTP a copy of my entire web site. Using a text editor that can do a full-text search of *all* files (I used UltraEdit), I searched for WP_POST_REVISIONS.

3. Found that it was being set to FALSE by a plugin – “postie” – on line 3 of postie-functions.php.

4. Edited that file and commented out the line. Made a backup on my local system where I backup the few plugin files that I have had to override/hack so I can reapply my hacks after updating the plugin if needed. The first few lines of the file should look like this:

<?php
$revisions= WP_POST_REVISIONS;
//define('WP_POST_REVISIONS', false);     <<-- Commented this line
//define('POSTIE_DEBUG', true);
if (!ini_get('safe_mode')) {

And voila… The Revisions meta box is visible again for posts and pages.