diff --git a/appveyor.yml b/appveyor.yml
index 6c0ae63..d24ca22 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -30,6 +30,8 @@ install:
   - IF %PHP%==1 echo extension=php_mbstring.dll >> php.ini
   - IF %PHP%==1 echo extension=php_fileinfo.dll >> php.ini
   - IF %PHP%==1 echo extension=php_curl.dll >> php.ini
+  - IF %PHP%==1 echo curl.cainfo=c:\tools\php74\cacert.pem >> php.ini
+  - IF %PHP%==1 curl --remote-name --time-cond cacert.pem https://curl.haxx.se/ca/cacert.pem
   - cd c:\projects\amphp
   - appveyor DownloadFile https://getcomposer.org/composer.phar
   - php composer.phar install --prefer-dist --no-progress