v4.0 "error on line 1 at column 6: XML declaration"

Could you please right click somewhere in the document and click “View Source”? It should start like this:

<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="https://www.arnebrachhold.de/wp-content/plugins/google-sitemap-generator/sitemap.xsl"?><!-- generator="wordpress/3.5.1" -->
<!-- sitemap-generator-url="https://www.arnebrachhold.de" sitemap-generator-version="4.0" -->
<!-- generated-on="March 30, 2014 18:11" -->
<sitemapindex xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xsi...

If there is anything before the <?xml, please let mew know.

It never fully loads to see

You should already be able to view the source, even it is not displayed correctly. Or please post a link to your site so I can try it.

hi,
me too being seen this problem on site game mobile: https://m.nguongame.com/
error on the url m.nguongame.com/sitemap.xml
error may be due to the theme. when using the default theme wp absolutely no problems. Because you see if that helps!

Thank you!

ductm, there is a new line at the beginning of the document. The theme should not be active on this page. Can you check if there is a newline in the functions.php of your theme?

Thank you

I’m trying to figure out the problem but not found. before update 4.0 it still works very well / sitemap.xml.

There is a new line. It was added because of what?
What can I do to find the problem?

The functions.php has not been updated for awhile for me. Using Genesis with a child theme.

https://firstgenfirebird.org/sitemap.xml

Last time I could not get my source to load was when I had a infinite loop in my code.

I have solved the error. you find any error or removing spaces and line behind?> in all php files.

hi everyone
my problem
give advice please

I found my issue was whitespace at the end of the file between the closing tag in my functions.php file. Just omit the end php closing tag ?> and remove all spaces after the last;

https://hardwiredmedia.com/error-on-line-1-at-column-6-xml-declaration-allowed-only-at-the-start-of-the-document-wordpress-rss-feed-issues/

“If a file is pure PHP code, it is preferable to omit the PHP closing tag at the end of the file. This prevents accidental whitespace or new lines being added after the PHP closing tag, which may cause unwanted effects because PHP will start output buffering when there is no intention from the programmer to send any output at that point in the script.”