A: 

Set AllowAutoRedirect to true on your HttpWebREquest instance.

x0n  2010-01-16 22:16:33
I did. It IS redirecting to the page that I need to click a submit button on. I just dont know how to post to the page it redirected me to. It makes me signin again when I try to directly access it.
Blankasaurus  2010-01-16 22:37:50
+1  A: 

Collect all the cookies from the previous (login) responses as at least one of them will be the cookie that tells Yahoo that you have already logged in. Then include the cookies with your post requst to the destination page, or any other interaction with Yahoo.

Edit: See this article for a complete code example for collecting and re-using cookies.
http://blogs.msdn.com/dgorti/archive/2005/08/16/452347.aspx

AUSteve  2010-01-16 23:11:26
Didn't work. =(
Blankasaurus  2010-01-17 02:46:15
When you set autoredirect to true does it collect cookies along its path? Like if it redirects and then redirects and redirects does it pick up cookies at each stop if there are cookies? Or do you have to do it manually? Either way I cant get this thing working.
Blankasaurus  2010-01-17 03:07:08
Use Fiddler (or some other HTTP debugging proxy) to capture the traffic from a normal login with a browser. Then confirm that your programmatic requests include the same cookies.
AUSteve  2010-01-17 06:48:34
Can't get it to work, but I imagine that this is the right answer.
Blankasaurus  2010-01-20 06:35:22
A: 

This is getting complicated.

The short answer seems to be Collect the Cookies. For some reason I fail at doing it though.

Blankasaurus  2010-01-17 03:16:16

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