IIS 7 and Above
The FastCGI Process Exited Unexpectedly
Re: The FastCGI Process Exited Unexpectedly
Apr 24, 2017 07:23 AM|Yuk Ding|LINK
To promise a wordpress plugin could works fine in IIS, you may need to check whether fast-cgi has been configured correctly:
Wordpress also have a dependency on MySQL, so please check whether you have configured the wordpress following this link:
If the steps above doesn't work, please check whether something wrong in php.ini extension list.
You could try to install
https://www.interactivewebs.com/blog/index.php/general-tips/windows-2012-r2-cprogram-files-x86phpv5-6php-cgi-exe-the-fastcgi-process-exited-unexpectedly-php/, the x86- vc++ distribution could also cause this issue.