I'm using the latest version of XAMPP which has PHP version 5.1.6
Everything (as far as XAMPP is concerned) is working fine.

However, I cannot get the debugger to work - it is not showing on phpinfo()

Here is what I have done so far;
Extraced the file from phped/debugger/server/Win32/i686/php_dbg.dll-5.1
Renamed the file to php_dbg.dll
Xampp has an extension directory call 'ext' (according to phpinfo) but it also has one called 'extensions' so I pasted the file into both locations.

In the php.ini file I added


Restarted apache after also altering the error reporting in php.ini to show start up errors and I get a warning saying it cannot find the module.
Zend is not loaded and all references to it are commented out in any event.

I'm assuming I have used the correct debugger file as I'm running apache under windows?

Any other suggestions as to what I can try.
phpEd is working fine using SVR but I really wanted to get it working (now I've paid for it lol ) with my XAMPP installation.

Any and all assistance is very much appreciated

Chances are you are editing a wrong php.in - php windows is actually known to pick up php.ini from c:\windows etc. PLease first see in phpinfo() output which php.ini is listed and make sure that is the one you are editing.
BTW - you don't have to rename the file, but that's fine as long as you entered the same name in php.ini

I have verified the location of php.ini both using XAMPP admin menu and by creating my own phpinfo() file - both files give the same path and confirm I was editing the correct file.
I was not certain which file I should be using as XAMPP is an apache server but XAMPP runs under Windows so I tried both and edited the extension= each time.
php.ini was edited and the debugger file placed on the server with Apache and mySQL shut down, then restarted after each attempt.

XAMPP also allows you to switch between it current PHP version (5.1.6) and 4.4.4 - I tried switching to 4.4.4 and this change is reflected in the phpinfo data. I also tried the relevant debugger files for that (after deleting the other one) and making the appropriate change in php.ini

Upon restarting XAMPP I still get the same 'Cannot load dynamic module....module not found'.

Obviously I am doing something wrong but just cannot figure out what it is.

Just to be absolutely certain of the php.ini file location I commented out the mySQL extension load and some others and those changes do get updated in phpinfo()

It may happen if you switched to php4 and trying to load debugger module compiled for php5. Or vice versa.
Just do not rename debugger modules and use appropriate dll in each case.

Regarding debugging functionality, please check Apache error_log. In most cases, it dumps out info if something goes wrong.
Also, if you have any other zend_extension_ts= (or zend_extension=) entries in your php.ini, you have to load debugger with the same entry, not with extension=blahblahblah. Please read FAQ on how to install debugger module.
Also should be noted that some zend_extension[_ts] modules may affect debugging functionality and in worse case prohibit from debugging at all.
In particular, such extension like APC or memcache or turk mmcache - all are caching php and debugger will not work for cached scripts.