PHP7卷曲设置

I have been trying to enable curl on PHP 7.1.4 which is running off of Apache HTTPD 2.4. The steps I have taken so far are:

1. Uncomment extension=php_curl.dll
2. Ensure that the ext path is set correctly (I have tested this by enabling openssl which works)
3. Adding the PHP root folder to my PATH environment variable

Although the function var_dump(extension_loaded('curl')); is false and curl is not listed under phpinfo();

I have run PHP --ri curl and it states: cURL support => enabled cURL Information => 7.53.1

I have also run deplister on the curl dll and it states that all lines are ok.

Please could you advise me of any other debugging steps or silly mistakes that I could have made (I feel that I have spent too many hours looking at this problem and a fresh set of eyes...)

More system info: Compiler MSVC14 (Visual C++ 2015) Architecture x64 Windows 7 platform

Edit I have also reinstalled all versions of c++ redistributable in order to rule out issues with dependences to no avail.