.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
Sign In
Win Surprise Gifts!!!

Top 5 Contributors of the Month
Gaurav Pal
Post New Web Links

Why do I get a 401 error when calling a WCF service from a web part?

Posted By:      Posted Date: September 15, 2010    Points: 0   Category :SharePoint
I have a SharePoint 2010 web part and WCF service deployed to a web application using Kerberos authentication. The service was developed based on the walkthrough from MSDN with the only difference that ClientCredentialType = HttpClientCredentialType.Windows so that Kerberos is used. The web application is being reverse-published through ISA. However we've never had an issue with this before. We've also disabled the loopback check on the server. When the web part calls the service, a 401 error occurs with the following exception message: The HTTP request is unauthorized with client authentication scheme 'Negotiate'. The authentication header received from the server was 'NTLM'. I configured Fiddler on the web application running the web part and found that both Kerberos and NTLM authentication headers are being returned: HTTP/1.1 401 Unauthorized Server: Microsoft-IIS/7.5 SPRequestGuid: 541e724c-85a7-47a0-b045-827e1c50793c WWW-Authenticate: Negotiate oXsweaADCgEBoQsGCSqGSIL3EgECAqJlBGNgYQYJKoZIhvcSAQICAwB+UjBQoAMCAQWhAwIBHqQRGA8yMDEwMDkxNDA1MjY1NlqlBQIDDgespgMCASmpDBsKREVDUy5MT0NBTKoXMBWgAwIBAaEOMAwbCnNwX3dlYmFwcDE= WWW-Authenticate: NTLM X-Powered-By: ASP.NET MicrosoftSharePointTeamServices: Date: Tue, 14 Sep 2010 05:26:56 GMT Content-Length: 0 Proxy-Support: Session-Based-Authentication Why then is the Kerberos authentication not a

View Complete Post

More Related Resource Links

Error calling WCF service that is returning list.".Debugging resource strings are unavailable ......

Ok.this is just making me frustrated... Here is step by step of what I am trying to do (& not able to) 1. I am calling WCF service hosted in a SharePoint 2010 site from a silverlight app in same domain (So no cross doman I guess). 2. I use Linq to Sharepoint for querying the DB. 3. I am having a list "machines" in Sharepoint 2010 that is having a lookup column from Other list called "part" 4. My WCF method GetAllMachines() works perfectly well when it skips the lookup column "partname" & returns List of type machineitem. 5. But problem occurs when I add machineitemobject.parts.partsname in my Linq to Sharepoint query . My service gives the error not found Async_ExceptionOccurred] Arguments: Debugging resource strings are unavailable." 6. Note that return type of my Method is List<machinesitem> 7. The point to note here is that I use SPMETAL tool to generate the LINQ class that maps the lists . So When I try to query the lookup column it tries to add List item of the type class & that is what causing the error. Is it because I am not using datacontract in my service (but it returns the strings & all private members of machines list e.g. name,title etc) Is it making the attribute Serialisable will solve the error ??? I am kind of lost in it ...Plss help!!   Thanks

Slow performance calling an Web Service in a Visual Web Part



I'm developing a report from data being served from a web service in SAP (through PI). I used the wsdl.exe to create a c# class and a wrapper and everything is working fine.

The problem is the performance... it takes about 3x the performance of an console application just to move the code inside a Visual Web Part.

I isolated the code to just this... 

DateTime timeReq = DateTime.Now;
response[] t = werbService.method(req);
double timeTaken = DateTime.Now.Subtract(timeReq).TotalMilliseconds;

It takes 60 seconds in a Visual Web Part and the same call in a console application takes 20s.

Since i dont have a packet sniffer i'm not sure why is taking so much time to execute the same code in sharepoint, am i missing some configuration? Anyone have face this kind of behaviour before?


Protocol error (503 Service unavailable) when calling webservice from Win2003


I'm receiving a 503 Service unavailable -error from a webservice when calling client is on WinServer 2003.

Scenario: Windows Forms (.NET 4) application calls remote webservice on windows server 2003 to fetch information.
In some cases it takes a long time for the WebService to get the informationa (long running database procedure) so the client waits for the response.
WebService timeouts are set at +30min.

The setup has worked fine for some time now but recently we discored that a particular long running request began to fail.
The Windows Forms client fails with a 503: Service Unavailable -error and ProtocolError after just a couple of minutes into waiting for the response.

We did some testing and this error occurs if the client application is installed on a Windows Server 2003 box.
If we do the same test with the client application installed on a Windows 7 box it works without errors.

It seems that it has something to do with Windows 2003 but how to debug this?
Anyone have any ideas what could be the problem?


Error calling Web Service. The remote server returned an error: (500) Internal Server Error


I am trying to extend my Sharepoing 2007 workflow using Ilove Sharepoint custom workflow actions. I have successfully installed ilove sharepoint exposing the ILOVE SHAREPOINT WORKFLOWS. the workflow however returns an error message 500 internal server error. When i try to access
the same using asp.net application it seems to work.

Web service code

using System;

using System.Collections.Generic;

using System.Linq;


Getting Error When Calling Wrokflow Service - The operation could not be performed because WorkflowI


The scenario .  ..

I have developed a Custom Activity(CA) which has a designer like SEQUENCE.

I created a Workflow Service (XAMLX) and placed my Custom Activity(CA) as the first activity. Then I placed a RECEIVE activity within this CA and provided all the necessary details.

Now if I run the workflow service and call the service operation it is throwing execption.

Failed to invoke the service. Possible causes: The service is offline or inaccessible; the client-side configuration does not match the proxy; the existing proxy is invalid. Refer to the stack trace for more detail. You can try to recover by starting a new proxy, restoring to default configuration, or refreshing the service.

The operation could not be performed because WorkflowInstance 'a74eb5e2-72b4-4cb1-8a4d-daed6f431936' has completed.

Instead if I put the original SEQUENCE activity as first activity and then placed a RECEIVE activity it is working good. But I don't want to use SEQUENCE activity here . .. . I need my custom SEQUENCE like activity to be the first activity and make this as a place holder for other activities.

Please help to get out of these errors.


Smart Client: Building Distributed Apps with NHibernate and Rhino Service Bus, Part 2


Smart client applications are responsive and promote interactivity with the user. In this article, we continue building a smart client application using NHibernate for data access and Rhino Service Bus for reliable communication with the server.

Oren Eini

MSDN Magazine August 2010

Service Station: Building a WCF Router, Part 2.


Here we present a deep look into the workings of Windows Communication Foundation routers, exploring the details of pass-through router implementations.

Michele Leroux Bustamante

MSDN Magazine June 2008

Service Station: Building a WCF Router, Part 1


Here we take a look at WCF clients and services, and explain how to tweak the addressing and message filtering behaviors so you can route services between them.

Michele Leroux Bustamante

MSDN Magazine April 2008

Service Station: An XML Guru's Guide to BizTalk, Part 2


In my last column, I provided a brief introduction to BizTalk® Server 2004 for XML developers (see Service Station: An XML Guru's Guide to BizTalk Server 2004, Part I). I covered the product evolution, core architecture, and several aspects of the underlying messaging layer, all of which have helped make BizTalk Server 2004 the powerful integration technology it is today.

Aaron Skonnard

MSDN Magazine December 2005

Service Station: An XML Guru's Guide to BizTalk Server 2004, Part I


Who would have believed that XML, such a seemingly trivial technology, could revolutionize an industry? It may have seemed like a long shot in the beginning, but the XML aficionados saw something special and pragmatic right away-a sort of duct tape for the world's information systems.

Aaron Skonnard

MSDN Magazine November 2005

.NET Framework-Part 2: Microsoft .NET Framework Delivers the Platform for an Integrated, Service-Ori


This article completes the .NET Framework overview begun in the September issue. The common language specification and ILDasm, the MSIL disassembler, are discussed-as well as how metadata, manifests, and assemblies simplify deployment and versioning. Security, which is integral to the design of .NET, is examined extensively, followed by a walk through the development of a single assembly containing multiple files. Finally, the way managed and unmanaged code work together, and the benefits of using each, including interoperablity with unmanaged code, are described.

Jeffrey Richter

MSDN Magazine October 2000

'Meter number is not registered ' error FedEx ship web service move to production



I want to integrate FedEx ship web service in my website. It works fine for local but for production it gives error. I changed test credentials by production credentials. also changed test url "https://gatewaybeta.fedex.com:443/webservices" by production url "https://gateway.fedex.com:443/webservices" But I am getting error that meter number is not registered. Please advice.

Custom tool error: Failed to generate code for the service reference 'CompanyService'. Please che


A little background because I feel I have an out of the ordinary architecture in place and don't know if this is contributing to the problem. 

We have an existing ASP.net application that is undergoing expansion.  The new functionality is all written in Silverlight 4.  As part of that expansion I gutted all the old Linq to SQL and put Entity Framework 4 into place.  To do this I created a standard .net Class Library and added my edmx files there.  Naturally, the business entities created by this cannot be used in Silverlight.  So I created a Silverlight Class Library and added all the business entities to that Silverlight Class Library as linked files.  I changed the name space to be the same.

So I have the following assembly / namespaces

Company.Project.Dal.csproj / Company.Project.Entities (.net 4 class library)

Company.Project.Entities.csproj / Company.Project.Entities (SL4 class library)

With this architecture I was able to share my business entities with my SL enabled web services, my asp.net projects, my silverlight projects.  Really it's a beautiful thing.

Once this was done I added "message" classes to Company.Project.Dal and again shared them with the other entites using linked files.  These messages are things like MyObjectRequest; they are class

"Your search cannot be completed because of a service error. Try ..."


i have a problem with search function where everytime i search any file/doc the error message "Your search cannot be completed because of a service error. Try your search again or contact your administrator for more information." occurred. I realized that there are items in central admin but it is "not available" in my site. I already follow several guides that had been provided in this forum but still the same. Even, i already create new SSP and configure the search scope, content source and also crawling. 

FYI, i used Microsoft Sharepoint 2007. 

Hope anyone could help me to solve this problem. Thanks.

RDL Rendering (500 Internal Server) Error at Sharepoint Integrated Reporting Service


I have a serious problem that cannot be solved by googling around the keywords below:
sharepoint, moss 2007, reporting service, ssrs 2008, rendering, internal server error, ....

The error is;

"An error occurred during client rendering. The remote server returned an error: (500) Internal Server Error. "

Everything is O.K.;

* When I render the report from the REPORTSERVER (http://localhost/ReportServer)
* When the reports are scheduled to be sent by the reporting service (planned via MOSS 2007) 

But if I open (render) the RDL file from the sharepoint REPORTS LIBRARY interface, all of the reports fail with that internal error message above. 

It is weird also that parametrized reports are displayed without errors although the parameters are queried from a sql dataset. But I got the error when rendering the report after I've chosen a parameter  and order "apply/report"...

Possible causes how I met that error may be;

After I have installed (then uninstalled) AJAX extensions
After I have re-configured IIS Web Service Extensions list items

Possible solution alternatives I've found;

I've found a solution on MSDN replying a similar issue with an ideal cause of the error but an evreka answer but no sol

SharePoint Calendar Error: The "ListViewWebPart" Web Part appears to be causing a problem. Index was

In one specific SharePoint calendar, on one specific week in that calendar when we select the "more items" link in the monthly view (or the expand all option) we get the following error:
The "ListViewWebPart" Web Part appears to be causing a problem. Index was outside the bounds of the array.

Web Parts Maintenance Page: If you have permission, you can use this page to temporarily close Web Parts or remove personal settings. For more information, contact your site administrator.
Troubleshoot issues with Windows SharePoint Services.

If we select a different week the expand and collapse works fine in that calendar.

Office 2010 Mobile Service Guidelines, Part 1

Learn how to build and host Web services for Office 2010 Mobile Service (OMS). This article introduces OMS architecture and the message flow between OMS Web service providers and clients.
ASP.NetWindows Application  .NET Framework  C#  VB.Net  ADO.Net  
Sql Server  SharePoint  Silverlight  Others  All   

Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend