XAMPP And The Freaken Apache Log Directory
Using XAMPP with multiple sites requires editing C:\xampp\apache\conf\extra\httpd-vhosts.conf. If it calls for logs like this: ErrorLog "C:\Users\John\Documents\My Webs\azenlab\logs\logs" you had better create the /logs directory or Apache will fail to restart. The bad thing is that none of the messages will give you an exact reason why.
Had the problem today while trying to get APC running on XAMPP and I had forgotten having the problem before. Hours wasted trying to figure why Apache wouldn't restart.