WANGXUYIN

1. save ca-bundle.crt to your local path
2. double click ca-bundler.crt to import it
3. add the two line to php.ini

curl.cainfo=d:/download/ca-bundle.crt  
openssl.cafile=d:/download/ca-bundle.crt

4. try to install composer-setup.exe agin.

refer to:https://github.com/composer/composer/issues/2798