My WordPress didn’t run and had strange error messages.
I tried everything possible until i’ve found the reason… Some Editors alter textfiles and add a BOM Byte Order Marker.
An editor added the BOM to the wp-config.php file and WordPress didn’t like it, that this php file wasn’t starting with normal php/html, but with some bytemarkers.
To resolve this i edited the file with a hex editor.
Copy & Paste into a new file might also help…