In the php.ini file you need to make sure the curl extension is enabled.
Find the following line in the php.ini file:
;extension=php_curl.dll
and remove the leading semi colon:
extension=php_curl.dll
then restart the php server.
Edit/Delete Message
i found these steps for enabling curl on wamp through Google:
1) Close WAMP (if running)
2) Navigate to WAMP\bin\php\(your version of php)\
3) edit php.ini
4) Search for curl, uncomment extension=php_curl.dll
5) Navigate to WAMP\bin\Apache\(your version of apache)\bin\
6) edit php.ini
7) Search for curl, uncomment extension=php_curl.dll
8) Save both
9) Restart WAMP