I have the exact same problem.
I tried to Add mime-types from file
And used an .ipcc file (iphone carrier bundle)
I tried to remove the plugin and reinstall it, but same error..
In Mime-type management:
Warning: Invalid argument supplied for foreach() in /customers/b/9/4/fixity.be/httpd.www/wp-content/plugins/pjw-mime-config/pjw-mime-config.php on line 187
And in the WordPress Download Monitor at Add New Download
when I want to upload a file:
Warning: array_merge(): Argument #2 is not an array in /customers/b/9/4/fixity.be/httpd.www/wp-content/plugins/pjw-mime-config/pjw-mime-config.php on line 254 Warning: Invalid argument supplied for foreach() in /customers/b/9/4/fixity.be/httpd.www/wp-includes/functions.php on line 2468