Can't upload .msg .xls file types (zendesk api)

[scooterbelasco]

Heyo, so I've ran into some problems uploading certain file types. Specifically .msg and .xls file types.

Background: I have a form with an uploads section that is being sent to Zendesk through their API.

When I upload one of these incompatible files the following happens ...

Console reads:

502 (Bad Gateway)
XMLHttpRequest cannot load {url-here} No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access. The response had HTTP status code 502.

Looking at Network I find 2 weird things:

1. under Response Headers

• files that don't work show
  Content-Type: text/html
• files that WORK show
  Content-Type: text/plain; charset=UTF-8

2. under Request Headers

• files that don't work show
  Content-Type: {empty}
• files that WORK show
  Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet

I have the

flowFactoryProvider.on('catchAll', function (event) {
      console.log('catchAll', arguments);
    });

on and It seems it drops off after uploadStart

Any ideas are welcome!

I'll try and get a plunker/fiddle up soon to show. Let me know if I can provide more info.