In some sites is unable to export the XML file

It might have to do with a plugin or theme using the filter the_generator to implement a custom “generator” meta tag. Authors are supposed to filter the output of that filter by type like get_the_generator does in order to avoid XML invalidities. If your XML file contains a line like <meta name="generator" content="anything" />, it won’t validate and BackWPup won’t process. It should be out-commented like i.e. <-- <meta name="generator" content="anything" /> -->.

Should have been <!-- <meta name="generator" content="anything" /> -->.

Hello Caspar. The problem is that the export process, from within BackWPup or from WP export tool, just stalls. No XML is generated, no matter how much time you wait.

I did a search from Linux for the string you told me. Hope it help:

# grep -H -r "the_generator" /home/rrhh/public_html/*
/home/rrhh/public_html/wp-admin/includes/export.php:<?php the_generator( 'export' ); ?>
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_html', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_xhtml', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_atom', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_rss2', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_rdf', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_comment', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-content/plugins/wordfence/lib/wordfenceClass.php:		add_filter('get_the_generator_export', 'wordfence::genFilter', 99, 2);
/home/rrhh/public_html/wp-includes/general-template.php:	the_generator( apply_filters( 'wp_generator_type', 'xhtml' ) );
/home/rrhh/public_html/wp-includes/general-template.php: * for a plugin to filter generators overall the the_generator filter.
/home/rrhh/public_html/wp-includes/general-template.php: * @uses apply_filters() Calls 'the_generator' hook.
/home/rrhh/public_html/wp-includes/general-template.php:function the_generator( $type ) {
/home/rrhh/public_html/wp-includes/general-template.php:	echo apply_filters('the_generator', get_the_generator($type), $type) . "\n";
/home/rrhh/public_html/wp-includes/general-template.php: * 'get_the_generator_{$type}' filter.
/home/rrhh/public_html/wp-includes/general-template.php: * @uses apply_filters() Calls 'get_the_generator_$type' hook.
/home/rrhh/public_html/wp-includes/general-template.php:function get_the_generator( $type = '' ) {
/home/rrhh/public_html/wp-includes/general-template.php:	return apply_filters( "get_the_generator_{$type}", $gen, $type );
/home/rrhh/public_html/wp-includes/default-filters.php:	add_action( $action, 'the_generator' );

FYI, Active plugins:
404 Redirected
AdRotate
Akismet
BackWPup
Better Feedburner Widget
Broken Link Checker
Cache Images
Changelogger
CloudFlare
Custom Login 2.0
Facebook
FeedBurner FeedSmith Extend
InfiniteWP – Client
Jetpack by WordPress.com
Jetpack Post Views
jQuery Colorbox
Relevanssi
Revision Control
Shareaholic | share buttons, analytics, related content
Simple Tags
TinyMCE Advanced
Wordfence Security
WordPress SEO
WP-Memory-Usage
WP-PageNavi
Wp Pagenavi Style
WP Super Cache

Just in case you’re wondering, it is not the only website where I use WordFence, CloudFlare and the other plugins… it is just the one where XML files are being unable to be exported.

Any ideas?

oh and BTW:

• I tried reinstaling WP 3.8: Nothing changed.
• I tried deactivating all the plugins and retrying XML export: Nothing changed.

WP 3.7 to 3.8 upgrade… same issues.

******
[26-Dec-2013 10:17:30] Database backup done!
[26-Dec-2013 10:17:30] 1. Trying to make a list of folders to back up …
[26-Dec-2013 10:17:33] 842 folders to backup.
[26-Dec-2013 10:17:33] 1. Trying to create a WordPress export to XML file …
[26-Dec-2013 10:17:34] WARNING: strpos(): Offset not contained in string
[26-Dec-2013 10:17:34] ERROR: Could not generate a WordPress export file.
[26-Dec-2013 10:17:34] 2. Trying to create a WordPress export to XML file …
[26-Dec-2013 10:17:34] 3. Trying to create a WordPress export to XML file …
[26-Dec-2013 10:17:35] Check WP Export file …
[26-Dec-2013 10:17:37] WP Export file is a valid WXR file.
[26-Dec-2013 10:17:37] Added XML export “xxxxx.xxxxxx.wordpress.2013-12-26.xml” with 717.70 kB to backup file list.
[26-Dec-2013
****

all plugins disabled (ALL of them) … default Twenty-Thirteen theme … deactivated and reactivated plugin…

I didnt try this with Twenty Thirteen nor Fourteen since the website is in production and a very visited one. I cant test another theme.
BTW, it’s using one from the Elegant Themes’ club.
I have several other sites with similar plugins and even themes by Elegant with no issues.
I cant tell why this is happenning to this one.

This issue is being noticed since WP 3.6. Wasnt fixed with 3.7 nor 3.8….

I started seeing this problem on one of my sites (WordPress 3.8, Apache 2.2.25, PHP 5.4.21, PageLines Free Theme) when I installed Jetpack by WordPress.com.

I found that by disabling the Enhanced Distribution component of Jetpack, all started working correctly again.

YMMV.

Kind Regards
Barry

@bazporter:
I tried deactivating Enhanced Distribution and didnt help to my site . Still unable to export XML files….

I just ran into this problem after a 3.8 upgrade to a multisite yesterday. Copying the job and deleting the original worked for me.

@jthomps123:
Copying the job and deleting the original worked for me too!!!!
Very smart!

Wow, that worked for me too. Thanks @jthomps123 !!!

I did notice prior to copying the job, that when it worked when I turned of the Wordfence Security Plugin… Not sure if that had anything to do with it.

@jthomps123: thank you for this workaround. now it worked for me too.

Any other ideas? I, too, have a website where this has started happening. Again Elegant Themes, and again I have other ET sites that are fine. Tried copying/deleting the job, and also deactivating WordFence – but no help.

With my site, the backup completes with errors. When I view the ZIP file, there is nothing in the root WP folder at all, just the three WP subdirectories.

Any idea would be much appreciated.

@mathewmackenzie: I found that in some servers you have to play with zip parameters from the configuration, and if your server does support php zip extension, it is one of the more reliable ones.

If you have other websites in the same server, be sure to copy exactly all of the Backwpup configurations. If that doesnt work, then retry deactivating every plugin and testing backwpup after activating one and every plugin, one at a time.

I also have several websites where still the xml file is unable to being genereated, but once I depleted my options, I just rely relaxed since at least the DB backup is being done fine. If you are not willing to move your site to another hosting service in the near future, you can forget about the xml file. Just be sure to keep backups of your DB and wp-content folder and you’ll be fine. ??

Hope it helps!