1、check the php inf..one by one.i'm sure .it's ok:
PHP 7.1+ with the following extensions: curl, dom, gd, json, mbstring, openssl, pdo_mysql, tokenizer, zip
2、chenk php.ini,and 4 sure,it's ok as noitamerd said. extension=php_fileinfo.dll
3、cd www\f and run cmd as adminstrastor:php composer.phar require intervention/image.for long long time.wait and wait .composer.json app..in www\f and cmd turn out:
4、cd www\f and run cmd as admin...and run ... no response...wait.... for long long time.turns out like this:
anything goes wrong? what can i do next?