Sharepoint Designer unable to open site

We installed a new instance of Sharepoint Foundation 2010 on a Windows 2008 server. Using Sharepoint Designer 2010 I am unable to connect to any site (or application) from that instance. The designer repeatedly prompts for credentials.

I tried running the designer from the server itself, but the problem remains the same.

Authentication with NTLM semms ok (as you can see below) because the request to _vti_inf.html is authenticated ok, but the request to shtml.dll still returns a 401 error.

Event viewer is empty, with all auditing options ON. Sharepoint logs shows nothing relevant.

Here are the requests captured with fiddler, during authentication:

GET /_vti_inf.html HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
Accept: */*
User-Agent: Mozilla/4.0 (compatible; MS FrontPage 14.0)
Host: dc-retail
Accept-Language: en-us, en;q=0.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Content-Length: 0
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}
Authorization: NTLM TlRMTVNTUAABAAAAB4IIogAAAAAAAAAAAAAAAAAAAAAGAbAdAAAADw==


HTTP/1.1 401 Unauthorized
Server: Microsoft-IIS/7.5
SPRequestGuid: 30b73f93-0dda-4605-b322-1e22c0981c33
WWW-Authenticate: NTLM TlRMTVNTUAACAAAADAAMADgAAAAFgomio3NFKpS4KUAAAAAAAAAAAJ4AngBEAAAABgGwHQAAAA9SAEUAVABBAEkATAACAAwAUgBFAFQAQQBJAEwAAQASAEQAQwAtAFIARQBUAEEASQBMAAQAGABSAEUAVABBAEkATAAuAEwATwBDAEEATAADACwARABDAC0AUgBFAFQAQQBJAEwALgBSAEUAVABBAEkATAAuAEwATwBDAEEATAAFABgAUgBFAFQAQQBJAEwALgBMAE8AQwBBAEwABwAIAH5V7/Pe38sBAAAAAA==
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:24:57 GMT
Content-Length: 0
Proxy-Support: Session-Based-Authentication


------------------------------------------------------------------
GET /_vti_inf.html HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
Accept: */*
User-Agent: Mozilla/4.0 (compatible; MS FrontPage 14.0)
Host: dc-retail
Accept-Language: en-us, en;q=0.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Content-Length: 0
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Authorization: NTLM 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
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}


HTTP/1.1 200 OK
Cache-Control: private,max-age=0
Content-Length: 247
Expires: Thu, 24 Feb 2011 11:24:57 GMT
Server: Microsoft-IIS/7.5
SPRequestGuid: 0afb45ea-a78e-4e96-adb8-efc6352aa666
Set-Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}; path=/
X-SharePointHealthScore: 0
Public-Extension: http://schemas.microsoft.com/repl-2
Set-Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}; path=/
Persistent-Auth: true
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:24:57 GMT

<!-- FrontPage Configuration Information 
FPVersion="14.00.0.000"
FPShtmlScriptUrl="_vti_bin/shtml.dll/_vti_rpc"
FPAuthorScriptUrl="_vti_bin/_vti_aut/author.dll"
FPAdminScriptUrl="_vti_bin/_vti_adm/admin.dll"
TPScriptUrl="_vti_bin/owssvr.dll"
-->

------------------------------------------------------------------
POST /_vti_bin/shtml.dll/_vti_rpc HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
User-Agent: MSFrontPage/14.0
Host: dc-retail
Accept-Language: en-us, en;q=0.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Content-Length: 42
Content-Type: application/x-www-form-urlencoded
X-Vermeer-Content-Type: application/x-www-form-urlencoded
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}

method=server+version%3a14%2e0%2e0%2e4730

HTTP/1.1 401 Unauthorized
Content-Type: text/html; charset=utf-8
Server: Microsoft-IIS/7.5
SPRequestGuid: 2397219c-28ce-48e5-b19b-2a223ba5ef33
Set-Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}; path=/
X-SharePointHealthScore: 0
WWW-Authenticate: NTLM
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:24:57 GMT
Content-Length: 16
Proxy-Support: Session-Based-Authentication

401 UNAUTHORIZED
------------------------------------------------------------------
POST /_vti_bin/shtml.dll/_vti_rpc HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
User-Agent: MSFrontPage/14.0
Host: dc-retail
Accept-Language: en-us, en;q=0.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Content-Length: 0
Content-Type: application/x-www-form-urlencoded
X-Vermeer-Content-Type: application/x-www-form-urlencoded
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}
Authorization: NTLM TlRMTVNTUAABAAAAB4IIogAAAAAAAAAAAAAAAAAAAAAGAbAdAAAADw==


HTTP/1.1 401 Unauthorized
Server: Microsoft-IIS/7.5
SPRequestGuid: 9fc97c50-976c-4d30-925d-f9126d9d9eb1
WWW-Authenticate: NTLM TlRMTVNTUAACAAAADAAMADgAAAAFgomiTAzoFYPLRCUAAAAAAAAAAJ4AngBEAAAABgGwHQAAAA9SAEUAVABBAEkATAACAAwAUgBFAFQAQQBJAEwAAQASAEQAQwAtAFIARQBUAEEASQBMAAQAGABSAEUAVABBAEkATAAuAEwATwBDAEEATAADACwARABDAC0AUgBFAFQAQQBJAEwALgBSAEUAVABBAEkATAAuAEwATwBDAEEATAAFABgAUgBFAFQAQQBJAEwALgBMAE8AQwBBAEwABwAIAN628fPe38sBAAAAAA==
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:24:57 GMT
Content-Length: 0
Proxy-Support: Session-Based-Authentication


------------------------------------------------------------------
POST /_vti_bin/shtml.dll/_vti_rpc HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
User-Agent: MSFrontPage/14.0
Host: dc-retail
Accept-Language: en-us, en;q=0.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Content-Length: 42
Content-Type: application/x-www-form-urlencoded
X-Vermeer-Content-Type: application/x-www-form-urlencoded
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Authorization: NTLM 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
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}

method=server+version%3a14%2e0%2e0%2e4730

HTTP/1.1 401 Unauthorized
Content-Type: text/html; charset=utf-8
Server: Microsoft-IIS/7.5
SPRequestGuid: e6cae461-0160-4396-b515-450ea71dd4b3
Set-Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}; path=/
X-SharePointHealthScore: 0
WWW-Authenticate: NTLM
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:24:57 GMT
Content-Length: 16
Proxy-Support: Session-Based-Authentication

401 UNAUTHORIZED
------------------------------------------------------------------
POST /_vti_bin/shtml.dll/_vti_rpc HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
User-Agent: MSFrontPage/14.0
Host: dc-retail
Accept-Language: en-us, en;q=0.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}
Content-Type: application/x-www-form-urlencoded
X-Vermeer-Content-Type: application/x-www-form-urlencoded
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Content-Length: 0
Authorization: NTLM TlRMTVNTUAABAAAAB4IIogAAAAAAAAAAAAAAAAAAAAAGAbAdAAAADw==


HTTP/1.1 401 Unauthorized
Server: Microsoft-IIS/7.5
SPRequestGuid: cbce22c8-c8dc-4ada-b1e8-4505847d5069
WWW-Authenticate: NTLM TlRMTVNTUAACAAAADAAMADgAAAAFgomi6SpBGgNKevwAAAAAAAAAAJ4AngBEAAAABgGwHQAAAA9SAEUAVABBAEkATAACAAwAUgBFAFQAQQBJAEwAAQASAEQAQwAtAFIARQBUAEEASQBMAAQAGABSAEUAVABBAEkATAAuAEwATwBDAEEATAADACwARABDAC0AUgBFAFQAQQBJAEwALgBSAEUAVABBAEkATAAuAEwATwBDAEEATAAFABgAUgBFAFQAQQBJAEwALgBMAE8AQwBBAEwABwAIAPYx8Pbe38sBAAAAAA==
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:25:02 GMT
Content-Length: 0
Proxy-Support: Session-Based-Authentication


------------------------------------------------------------------
POST /_vti_bin/shtml.dll/_vti_rpc HTTP/1.1
Date: Fri, 11 Mar 2011 11:25:54 GMT
MIME-Version: 1.0
User-Agent: MSFrontPage/14.0
Host: dc-retail
Accept-Language: en-us, en;q=0开发者_如何学C.1
Accept: auth/sicily
X-FORMS_BASED_AUTH_ACCEPTED: T
Authorization: NTLM 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
Content-Type: application/x-www-form-urlencoded
X-Vermeer-Content-Type: application/x-www-form-urlencoded
Accept-encoding: gzip, deflate
Connection: Keep-Alive
Pragma: no-cache
Content-Length: 42
Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}

method=server+version%3a14%2e0%2e0%2e4730

HTTP/1.1 401 Unauthorized
Content-Type: text/html; charset=utf-8
Server: Microsoft-IIS/7.5
SPRequestGuid: 4aa92f6a-85fa-49ea-ba7e-b2a877674b99
Set-Cookie: WSS_KeepSessionAuthenticated={0fd9a89e-7284-4d62-a243-83e74c767a47}; path=/
X-SharePointHealthScore: 0
WWW-Authenticate: NTLM
X-Powered-By: ASP.NET
MicrosoftSharePointTeamServices: 14.0.0.4762
Date: Fri, 11 Mar 2011 11:25:02 GMT
Content-Length: 16
Proxy-Support: Session-Based-Authentication

401 UNAUTHORIZED
------------------------------------------------------------------

In my case, the problem was caused by a custom IIS Http Module, who was doing some checking on request form variables. It was only checking if HttpRequest.Form property <> null, and it seems this type of check crashes the request made by Sharepoint Designer.

Please check if your user has sufficient rights to login on SharePoint site. Can you open it in browser?

Have you allowed SharePoint Designer to connect to the web application from within Central Administraton?