Error Messages at Log In

For the ones that start with ‘deprecated’ see this article about PHP error reporting. I’d suggest editing the php.ini file and turn off notices. Leave errors. You want those.

Something odd is going on with the others. Something is echoing content before the http headers are sent. That’s not supposed to happen. It might even be those warnings that are triggering the other errors. Turn off any plugins and switch to the default theme. If it clears up, start turning things on one by one until you find the culprit.

Hi apljdi,

you did not include a link. Could this be caused if I have yet to download a theme?

Sorry.

You should have the WP default theme at least. But no, I don’t think this is a due to the lack of a theme. Like I said, the deprecated messages are part of PHP’s error reporting system. The other messages are most frequently caused by stray characters in your wp-config.php. Uncommented text or invisible control characters left by Word Processors will cause that error. Usually, though, wp-config.php shows up in the error message if that’s the case. Its odd to have the error in wp-setting and in pluggable, still, it doesn’t hurt to check wp-config anyway. Sometimes errors can cascade. Make sure you edit wp-config with a text editor not a word processor.

I do receive similar error messages when I try to log in the first time after installation. The main page is looking the way it should, the login-page shows these messages:

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-login.php on line 255

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-login.php on line 267

However, theres stil the login-form on that page, so I tried to proceed:
When I try to log in, I get these messages instead of the admin panel:

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-login.php on line 255

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-login.php on line 267

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-includes/pluggable.php on line 658

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-includes/pluggable.php on line 659

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-includes/pluggable.php on line 660

Warning: Cannot modify header information - headers already sent by (output started at xxx/html/wordpress/wp-config.php:1) in xxx/html/wordpress/wp-includes/pluggable.php on line 850

I already checked the wp-config for the errors you pointed out (with texteditor) but couldn’t find any. Any ideas whats wrong?
Regards

Problem is solved.
There seems to be a problem with the translated german version of the wp-config. When I uploaded the english version it worked.

Sometimes, this problem is due to emergency update of apache on server. One other thing that you can do is ask your hosting provider to recompile apache and see whether the php version is correct.