zerochaos

I also had the same problem after installing WordPress 2.7. Solved the problem as follows:
1. Create a folders in ‘wp-admin’ ‘wp-content/uploads’
2. Open wp-includes/functions.php and replace

function path_is_absolute( $path ) {
	// this is definitive if true but fails if $path does not exist or contains a symbolic link
	if ( realpath($path) == $path )
		return true;

with

function path_is_absolute( $path ) {
	// this is definitive if true but fails if $path does not exist or contains a symbolic link
	if ( realpath($path) != $path )
		$path == realpath($path);
	else
		return true;

That’s all! All files will now be filled in wp-content/uploads. Enjoy!