Hi,
my configuration is:
Win2003, IIS6, PHP 5.03 and ZendOptimizer 2.5.7 (Engine v2.0.3)
I downloaded the DBG archive for windows und unzipped it. I got 2 directories: i386 and i686. Then I copied the 5.0.3-dll (equal from i386 or i386) with the name php_dgb.dll in the extension directory of PHP. In php.ini I added the entry for the dll (extension=php_dbg.dll) and the entries for [debugger] like described in 'configuring server part'.
On calling a php-page I get "Warning: Module 'Zend Optimizer' already loaded" in eventlog of the server and the browser gets cgi-error.
On commenting out the entry for extension all works fine.
What did I do wrong?
Regards
Gaby

extension=php_dbg.dll can't be used in this case. Please follow these instructions:
howto-install-debugger-module-t576.html#2261

thanx for information. It works fine, but you have to consider the order of entries - first for dbg and than for zend.