I think you need to update it to the latest version. Should be in your WordPress updates list.

Hi Yellow Swordfish,

thank you very much, but I use simple:press Version 5.5.4 and Google XML-Sitemap 2.3.2.
I think these are the newest versions?

Best regards, Kalle

Curious… Are you using the most recent version of Yoast as well?

A user reported a problem with dates prior to our 5.5.4 release which was fixed and released in the GSP 2.3.2 release and verified as corrected at that time. 

Yes, also Yoast is the newest version.

A weird thing is:

If I have a look at: http://vogel-beobachtung.de/sitemap_index.xml

…the time format is in the “wrong” format, but if I visite:

http://vogel-beobachtung.de/forum-sitemap.xml

..the format is well. Might that be a bug?

Best regards, Kalle

I am sorry to say that our Google Sitemap, SEO and Yoast team member is on vacation at the moment so I am ill-equipped to know. I am going to find the thread that raised the date issue in the first place to see if there is any information that might help. Will post back in a little while.

here is the thread: https://simple-press.com/support-forum/sp5-general-topics/yoast-sitemap-invalid-date-format/

I don’t know if that helps but does it sound like a similar issue? The latest code you are using does have this change in it.

HI Yellow Swordfish,

thank you very much. That was a good help.

I changed:

function sp_google_sitemap_do_generate_yoast_main() {
    $map = ”;

    $base = $GLOBALS[‘wp_rewrite’]->using_index_permalinks() ? ‘index.php/’ : ”;
    $date = spdb_table(SFPOSTS, ”, ‘UNIX_TIMESTAMP(post_date)’, ‘post_date DESC’, ‘1’);
    $map.= ‘<sitemap>’.”
“;
    $map.= ‘<loc>’.home_url($base.’forum-sitemap.xml’).'</loc>’.”
“;
    $map.= ‘<lastmod>’.date($date).’ </lastmod>’.”
“;
    $map.= ‘</sitemap>’ . “
“;

    return $map;
}

Into:

function sp_google_sitemap_do_generate_yoast_main() {
    $map = ”;

    $base = $GLOBALS[‘wp_rewrite’]->using_index_permalinks() ? ‘index.php/’ : ”;
    $date = spdb_table(SFPOSTS, ”, ‘UNIX_TIMESTAMP(post_date)’, ‘post_date DESC’, ‘1’);
    $map.= ‘<sitemap>’.”
“;
    $map.= ‘<loc>’.home_url($base.’forum-sitemap.xml’).'</loc>’.”
“;
    $map.= ‘<lastmod>’.htmlspecialchars(date(‘c’, $date)).'</lastmod>’.”
“;
    $map.= ‘</sitemap>’ . “
“;

    return $map;
}

…now it works

Wow! That IS good news. I will pass this thread on to @mr-papa when he returns…

Thanks for the update and glad it was easily sorted.

odd.. at first blush (and just back from 2 week cruise!), not sure why the change would be needed…

but will investigate it…

something amiss here… will get it fixed up… ticket open…