How to fix PHP Warning: PHP Startup: Unable to load dynamic library 'ext\\php_curl.dll'?
As Darren commented, Apache don't understand php.ini relative paths in Windows.
To fix it, change the relative paths in your php.ini to absolute paths.
extension_dir="C:\full\path\to\php\ext\dir"
Use absolute path:
extension_dir="C:\full\path\here"