NTLM failure

[John Lee]

Hi,

I have a virtual directory configured as "integrated windows authentication"
and "anonymous acccess" is turned off. I can use IE to acccess that page but
when I try to access the page using

HttpWebRequest wr = (HttpWebRequest ) System.Net.WebR equest.Create(u rl);
wr.Credentials = CredentialCache .DefaultCredent ials;
HttpWebResponse resp = (System.Net.Htt pWebResponse)wr .GetResponse();

I got "System.Net.Web Exception: The remote server returned an error: (401)
Unauthorized." error, Any idea why?

Thanks very much!
John

[Steven Cheng[MSFT]]

RE: NTLM failure

Hi John,

Glad to see you again :-).

As for the 401 error you encountered when requesting page protected by
integrated windows authentication through
HttpWebRequest component, it is because the HttpWebRequest component won't
automatically provide the client side credential (from the current logon
user like what IE does). So we need to manually attach the credential if
the serverside dosn't allow anonymous accessing. For example, the following
code snippet just provide a credential (NTLM auth schema):

=============== ======
NetworkCredenti al myCred = new NetworkCredenti al(
"username","pas sword","domain or machine name");

CredentialCache myCache = new CredentialCache ();

myCache.Add(new Uri("www.contos o.com"), "NTLM", myCred);


WebRequest wr = WebRequest.Crea te("www.contoso .com");
wr.Credentials = myCache;
...............
=============== =======

Here is the MSDN reference on System.Net.Netw orkCredential class:

http://msdn.microsoft.com/library/en-us/cpref/html/frlrfsystemnetnetworkcred

entialclasstopi c.asp?frame=tru e

Hope helps. Thanks,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)

[John Lee]

Re: NTLM failure

Thanks Steven!

But I need to use the current logon user's credential to access that page
and
the following code should work - but it does not work for me:

wr.Credentials = CredentialCache .DefaultCredent ials;

Another thing I noticed that might be related, I created a virtual directory
"test" with "windows integrated authentication" only on a 2003 server
"server1" with SP1 box.
step 1. open a new instance of IE, access http://server1/test it will popup
asking for username/password, type in password and it will work
2. IF i add http://server1 into local intranet zone, repeat step 1, no popup
to ask password

I tested the above scenario on several box and it's consistent. so my
another question is that when we use HttpWebRequest to access the virtual
directory by using logon user's network credential - how to configure the
accessed uri is in local intranet zone from code or it SHOULD grab that
setting done by IE?

Thanks!
John



"Steven Cheng[MSFT]" <v-schang@online.m icrosoft.com> wrote in message
news:tZuerc5VFH A.2828@TK2MSFTN GXA01.phx.gbl.. .[color=blue]
> Hi John,
>
> Glad to see you again :-).
>
> As for the 401 error you encountered when requesting page protected by
> integrated windows authentication through
> HttpWebRequest component, it is because the HttpWebRequest component won't
> automatically provide the client side credential (from the current logon
> user like what IE does). So we need to manually attach the credential if
> the serverside dosn't allow anonymous accessing. For example, the
> following
> code snippet just provide a credential (NTLM auth schema):
>
> =============== ======
> NetworkCredenti al myCred = new NetworkCredenti al(
> "username","pas sword","domain or machine name");
>
> CredentialCache myCache = new CredentialCache ();
>
> myCache.Add(new Uri("www.contos o.com"), "NTLM", myCred);
>
>
> WebRequest wr = WebRequest.Crea te("www.contoso .com");
> wr.Credentials = myCache;
> ..............
> =============== =======
>
> Here is the MSDN reference on System.Net.Netw orkCredential class:
>
> http://msdn.microsoft.com/library/en...netnetworkcred
> entialclasstopi c.asp?frame=tru e
>
> Hope helps. Thanks,
>
> Steven Cheng
> Microsoft Online Support
>
> Get Secure! www.microsoft.com/security
> (This posting is provided "AS IS", with no warranties, and confers no
> rights.)
>
>
>[/color]

[Steven Cheng[MSFT]]

Re: NTLM failure

Thanks for your respones John,

As for the further question you mentioned, here are my understandings:

1. YES, IE will automatically send the current logon session's credential
when accessing trusted or intranet zone sites and
anonymous access is not allowed. We can also verfify this in the IE's
Tools---->Internet Options--->Security---->certain Zone ---> Custom Level
setting---> UserAuthenticat ion. Logon

2.When using HttpWebRequest, it has nothing related to IE setting. So we
will always need to manually provide the credential when accessing remote
resouce when require authentication. And yes, the
System.Net. CredentialCache .DefaultCredent ials contains the current logon
user's credential (in winform or console app), but if this credential is
not valid on the remote server, the request will also fail. Different from
IE( IE will popup authentication dialog to let us input username/password
when current user is not valid on remote server), using httpwebrequest ,
there is no such dialog.

So as for your scenario, I think the problem is your current logon user is
not a valid account on the remote server. Is your logon user account a
local account on the machine where you running the httpwebrequest app? If
so, this account is not valid to the remote server, you need to provide a
valid account on the remote server , this account can be either of :
1. A domain account

2. A duplicated local account which has same username/password on both
client and server machine.

Thanks,

Steven Cheng
Microsoft Online Support

Get Secure! www.microsoft.com/security
(This posting is provided "AS IS", with no warranties, and confers no
rights.)