Why does JavaScript only work after opening developer tools in IE once?

Question

IE9 Bug - JavaScript only works after opening developer tools once.

Our site offers free pdf downloads to users, and it has a simple \"enter password to download\" f

Answer 1

If you are using angular and ie 9, 10 or edge use :

myModule.config(['$httpProvider', function($httpProvider) {
    //initialize get if not there
    if (!$httpProvider.defaults.headers.get) {
        $httpProvider.defaults.headers.get = {};    
    }    

    // Answer edited to include suggestions from comments
    // because previous version of code introduced browser-related errors

    //disable IE ajax request caching
    $httpProvider.defaults.headers.get['If-Modified-Since'] = 'Mon, 26 Jul 1997 05:00:00 GMT';
    // extra
    $httpProvider.defaults.headers.get['Cache-Control'] = 'no-cache';
    $httpProvider.defaults.headers.get['Pragma'] = 'no-cache';
}]);

To completely disable cache.