I have uncomment the following from the php.ini file
;extension=php_bz2.dll
extension=php_curl.dll
;extension=php_dba.dll
Also ,I have cop
Had same issue with 64 bit Windows 7. This is what worked for me.
Answered by Soren from another SO thread - CURL for WAMP
"There seems to be a bug somewhere. If you are experiencing this on Win 7 64 bit then try installing apache addon version 2.2.9 and php addon version 5.3.1 and switching to those in WAMP and then activating the CURL extension. That worked for me."