If you receive this error, and you are running WAMP or similar web environment on 64-bit Windows 7, this may help solve your problem. If you have already tried enabling php_curl.dll and everything looks good within your php.ini files (extension=php_curl.dll and not ;extension=php_curl.dll) but CURL doesn’t show up when you call phpinfo(), you will need to download a different version of php_curl.dll.
You can go here: http://www.anindya.com/
The download you are looking for is under the list of ‘Fixed curl extensions’: php_curl-5.3.13-VC9-x64.zip
Extract that archive and then overwrite /wamp/bin/php/php5.3.13/ext/php_curl.dll with the one you downloaded. We suggest renaming the current php_curl.dll file just in case you need to revert.
Hope this helps!