If you have encountered feed validation errors with Wordpress plugins you may find this useful.

1. The problem

The problem you may know is that an advanced Wordpress installation (say: having many plugins and customized pages installed) can results in an invalid Feed-Validation like this:

This feed does not validate.
line 1, column 1, XML parsing error: 1:1: xml declaration not at start of external entity

^

The Feedvalidator returns a XML Parsing Error marking a whitespace before the first xml-tag. Nobody knows where this comes from…right?

2. The source

…may be in any of your Wordpress Plugin files. The XML-Feed Validation error simply results from leading or trailing whitespaces in any of your wp-plugin’s *.php file.

3. The solution

To fix the validation error switch off your plugins one by another to see in which script the bug is in. (switch off>validate…etc.)
If you spotted the ‘buggy’ plugin-file check it for leading or trailing whitespace before and after the -Tags. Simply delete them with a text-editor of your choice and also make sure that there aren’t any blank lines outside the script tags.

4. Validation

When the work is done you will be rewarded with a valid feed.

Congratulations!

This is no big deal, but I think this only happens because users create these files from scratch in a text-editor just by pasting selected php-code from a plugin’s webpage or customizing the plugin a bit (assuming the plugin is originally well-formatted).

So take care of your whitespaces. Hope this helps.

Posted in Wordpress, Tags:feed, validation, Wordpress

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