The mime_content_type function posted above (the modified version, that is) follows this execution path:
1. If the mime_content_type function exists, use it. (This function does not exist in your version of PHP.)
2. Otherwise, if the fileinfo extension exists, use it. (This function does not currently exist in your version of PHP, but should be installed.)
3. Otherwise, try to execute the external "file" utility. (This function is a *NIX standard utility but does not exist in Windows.)
The only step that requires external execution privileges is the third, which is not relevant to your system if you've got the fileinfo extension installed. Besides, it's much better to use the internal tool for performance reasons. I'd suggest investigating why the fileinfo functions aren't installed; it will make execution permissions irrelevant.
Open Journal Systems Team
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