I\'m using PHP5, CodeIgniter and Apache. The localhost php pages were loading fine and then suddenly they started crashing Apache.
The web pages seem to get to diff
In my case it was the php extension APC (php_apc.dll, 3.1.10-5.4-vc9-x86, threadsafe), which caused the error.
I used XAMPP 1.8.2 with PHP 5.4.19 and Apache 2.4.4
Since it could be caused by another extension as well, it might be a good starting point to restore the original php.ini from the xampp distribution. If this one works well, try to change it line by line to your desired configuration (starting with the extension list).