No 'Access-Control-Allow-Origin' header is present on the requested resource + The response had HTTP status code 401

XMLHttpRequest cannot load http://192.168.1.253:8080/... No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:4200' is therefore not allowed access. The response had HTTP status code 401.

Pretty common error, with a great many possible solutions that haven't worked. I understand (I think) how CORS is supposed to work, and I don't see anything wrong with my HTTP headers, but it still doesn't work

From Chrome:

Request URL:http://192.168.1.253:8080/...
Request Method:OPTIONS
Status Code:200 OK
Remote Address:192.168.1.253:8080
Referrer Policy:no-referrer-when-downgrade
Response Headers
Access-Control-Allow-Headers:x-requested-with,accept,content-
type,authorization
Access-Control-Allow-Methods:POST, GET, PUT, PATCH, OPTIONS, DELETE
Access-Control-Allow-Origin:*
Access-Control-Max-Age:3600
Allow:GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS, PATCH
Cache-Control:no-cache, no-store, max-age=0, must-revalidate
Connection:keep-alive
Content-Length:0
Date:Mon, 15 May 2017 21:50:55 GMT
Expires:0
Pragma:no-cache
Server:...
X-Content-Type-Options:nosniff
X-Frame-Options:DENY
X-XSS-Protection:1; mode=block
Request Headers
Accept:*/*
Accept-Encoding:gzip, deflate, sdch
Accept-Language:en-US,en;q=0.8
Access-Control-Request-Headers:authorization,content-type
Access-Control-Request-Method:GET
Cache-Control:no-cache
Connection:keep-alive
Host:192.168.1.253:8080
Origin:http://localhost:4200
Pragma:no-cache
Referer:http://localhost:4200/...
User-Agent:Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 
(KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36

My understanding is the OPTIONS response needs the Access-Control-Allow-Origin header set and allow the method type and header values, which it does

Relevant angular below. I've done a fair number of different combinations of this with all sorts of different stuff in the header, but nothing works

private getObject<T>(path: string): Promise<T> {
    return this.http.get(SERVER_URL + path, this.authenticationToken())
        .toPromise()
        .then(response => response.json() as T)
        .catch(this.handleError);
}

private authenticationToken() : RequestOptions {
    let login = JSON.parse(sessionStorage.getItem('currentLogin'));
    if (login && login.authenticationToken) {
        let headers = new Headers({ 
            'Authorization': 'Basic ' + login.authenticationToken,
            'Content-type': 'application/json', 
          });
        return new RequestOptions({ headers: headers });
    }
}

I got the feeling I'm missing something obvious but it's driving me nuts, any help is appreciated. Note this does work with a pre-existing Ember application so I don't think it's the server