It finally is a wrong directive in /public_html/pub/media/.htaccess.
Comment this: #Options -ExecCGI
Yes, it will happen if you use the Windows platform instead of Linux.
Because in Magento 2 recent release, they have introduced the Symlink option (Like shortcut of an existing file) to copy from code directory to pub directory.
Unfortunately, the Windows platform needs special permission to create symlink files. So you need to stop your server and your command prompt terminal then we need to start the server and terminal with the administrator access.
Then simply delete "adminhtml" and "frontend" folders from "pub/static" directory.
Then do setup upgrade using "php bin\magento setup:upgrade".
Flush the cache once using "php bin\magento cache:flush"
I hope the problem is resolved now. If it works kindly give me kudos.
This error is due to the wrong path to the pub/static folder
Go to General/Web and write the correct path in the secure and unsecure tab.