OK, thanks, that works so far. It gives me a session ID.

How do I pass the cookie with the header? WWWForm.headers is readonly, which makes this not work:

    WWWForm loginCookie = new WWWForm();
    loginCookie.headers = loginQuery.responseHeaders;
    Debug.Log("Loading game...");
    WWW myGame = new WWW("http://www.conquerclub.com/game.php?game="+gameID, loginCookie);

I tried this (sessionID is a string that looks like: "PHPSESSID=fvcrj18e9b7hr4tlb91hv1mhj6" (using the data pulled out of loginQuery.responseHeaders)

       WWWForm loginCookie = new WWWForm();
    loginCookie.AddField("Cookie", sessionID);
    Debug.Log("Loading game...");
    WWW myGame = new WWW("http://www.conquerclub.com/game.php?game="+gameID, loginCookie);

But this gives me a WWW.error if "necessary data rewind wasn't possible"

If you need to use WWWForm, you have to combine the headers created by the WWWForm and add your additional ones and finally use the WWW constructor that takes 3 parameters:

WWWForm myPostData = new WWWForm();
myPostData.AddField("your user data", data);

Hashtable headers = myPostData.headers;
headers.Add("Cookie",sessionID);

WWW myGame = new WWW("http://www.conquerclub.com/game.php?game="+gameID, myPostData.data, headers);

If you actually don't need post data and just want to use a GET request pass null as post data.

Hashtable headers = new Hashtable();
headers.Add("Cookie",sessionID);

WWW myGame = new WWW("http://www.conquerclub.com/game.php?game="+gameID, null, headers);

Haven't tested or compiled it, just wrote it from scratch but should work that way.

Hmm, since the WWWForm.headers is a Hashtable (so it's a reference type) i guess you can just add your "Cookie" field and use the form directly as well. Read only means you can't set a new Hashtable to the property, but you can add fields to the hashtable itself.

WWWForm myPostData = new WWWForm();
myPostData.AddField("your user data", data);

myPostData.headers.Add("Cookie",sessionID);

WWW myGame = new WWW("http://www.conquerclub.com/game.php?game="+gameID, myPostData);

I'm trying to figure out how the hell the real webpage even knows what session it is. I assumed the page sent cookies in the request, but inspecting the request header in Safari (while logged in)....

Origin: http://www.conquerclub.com

Accept-Encoding: gzip, deflate

Accept-Language: en-us

User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_3) AppleWebKit/534.55.3 (KHTML, like Gecko) Version/5.1.5 Safari/534.55.3

Accept: text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8

Cache-Control: max-age=0

Referer: http://www.conquerclub.com/public.php?

mode=login&redirect=game.php%3Fgame%3D11087909

Nothing! I don't know a lot about the subject of HTTP and cookies and such... I have no idea how the CC webpage server knows that I'm me when I go there in the browser. Any ideas where else I could look?

I just registered myself on this site and i guess your problem is that the page uses several Set-Cookie headers.

The problem with multiple Set-Cookie headers is that Unity uses a Hashtable to store the response headers. Hashtables provide easy access to the headersfields, but each header can only exist once. If there are two or more Set-Cookie headers they overwrite themselves and only the last one will survive.

There is already a feature request on this issue

update
I've just checked what happens when i visit the page without any set cookie. At the first visit i get those:

Set-Cookie: referer=**my referer**; path=/
Set-Cookie: referer60=**my referer**; expires=Wed, 20-Jun-2012 01:50:00 GMT; path=/
Set-Cookie: PHPSESSID=**my session ID**; path=/; HttpOnly

at once. Unity would discard two of them, usually it keeps the last one.

The only way around this is to not use the WWW class at all ;) Use the .NET classes