Have you modified your functions.php file at all? I had the same problem with the ‘dreaded white screen’ when creating new posts and after logging out. My problem lay with the following code which limits the number of words displayed in excerpts.
<?php
function string_limit_words($string, $word_limit)
{
$words = explode(' ', $string, ($word_limit + 1));
if(count($words) > $word_limit)
array_pop($words);
return implode(' ', $words);
}
?>
If anyone has used the same code and is encountering a white screen, removing it from functions.php should get your admin back.
Any suggestions welcomed for incorporating this code safely or other methods of limiting excerpts.