This article describes, how to fix RSS Feed error messages in WordPress.
In Firefox the error is “XML Parsing Error”. In IE you see “Internet Explorer cannot display this feed”.
When you click on RRS link in WordPress (or bbPress), you are getting this error message (see images bellow). The message is different depending on your browser.
|XML Parsing Error: XML or text declaration not at start of entity
Line Number 4, Column 1:<?xml version=”1.0″ encoding=”UTF-8″?>
|Internet Explorer cannot display this feed
This feed contains code errors.
Go back to the previous page.
Invalid xml declaration.
<?xml version=”1.0″ encoding=”UTF-8″?>
Look at the page source code in the browser, and see how many blank lines you have at the top of the page:
These blank lines on your HTML page source code could appear from blank lines between PHP tags in your WordPress theme functions.php file:
The problem here is the white space between PHP tags, not the space inside PHP code. To fix the problem, remove that blank space, or better yet make it one PHP tag.
Reload your WordPress page and see, if any blank lines remain at the top. If yes, continue the search. Even white space after the last PHP tag needs to be removed.
You also might have a custom “functions.php” in your bbPress template. That file also should be checked for white space. If you wrote some custom plug-ins, check the code there as well.