Getting the error below in your eventlog and do you have multiple identities for your website (i.e: sample.domain.tld & localhost)?

Event Type:        Error
Event Source:     System.ServiceModel 3.0.0.0
Event Category: WebHost
Event ID:           3
Date:                 16-9-2009
Time:                 8:46:15
User:                  NT AUTHORITY\NETWORK SERVICE
Computer:          COMPUTERNAME
Description:
WebHost failed to process a request.
Sender Information: System.ServiceModel.ServiceHostingEnvironment+HostingManager/40535505
Exception: System.ServiceModel.ServiceActivationException: The service '/Sample/SampleService.svc' cannot be activated due to an exception during compilation.  The exception message is: This collection already contains an address with scheme http.  There can be at most one address per scheme in this collection.

You could solve this issue by adding the following config section to your web.config:

    <system.serviceModel>
        ...
        <serviceHostingEnvironment>
            <baseAddressPrefixFilters>
                <add prefix="http://sample.domain.tld/Sample/"/>
            </baseAddressPrefixFilters>
        </serviceHostingEnvironment>
        ...
    </system.serviceModel>

Receiving the the above message while trying to test your .NET web service remotely? Try to add the follwing xml snippet in the right place of your web.config file.

<system.web>
    <webServices>
        <protocols>
            <add name="HttpGet"/>
            <add name="HttpPost"/>
        </protocols>
    </webServices>
</system.web>

happy coding :)

At this moment I'm building different kind of webparts for MOSS 2007. Some of these webparts are using the nice new fancy .Net 3.5 stuff. Because webparts are running in the SharePoint context you need to upgrade SharePoint to .Net .5 to get it to work.

Thanks to Jan Tielen I found an easy way to do this, hereby the 6-step tutorial:

• Start Visual Studio 2008.
• Create a new dummy ASP.NET Web Application Project, and make sure you target the .NET Framework 2.0 (upper right dropdown of the New Project dialog). The name of this project is not important; you won’t need it anymore when we’re done.
• Copy the web.config of your SharePoint 2007 site, into the dummy Web Application project in Visual Studio.
• Open the Project Properties in Visual Studio (right click on the Project node in the Solution Explorer, and choose Properties; or in the Project menu, select WebApplicationX Properties).
• Select .NET Framework 3.5 in the Target Framework dropdown (select Yes in the confirmation dialog).
• Copy the web.config from the Web Application Project back to SharePoint.

After doing this I did some testing inside SharePoint. Everything seemed to work. Until the next day...

The day after I needed to some things with my 'favorite tool' "SharePoint designer". I connected to my test-machine and try to open a aspx-file inside the designer (the application tree was shown as normal). I got the following error:

The server sent a response which SharePoint Designer could not parse. If you are trying to connect to a Windows SharePoint Services server, check with the server's administrator to make sure Windows SharePoint Services is installed properly.

Because I just upgraded the to .NET 3.5 , I knew the cause would be somewhere in the web.config file. After some digging  found out that inside the httpHandlers something went wrong:

<httpHandlers>
    <remove verb="GET,HEAD,POST" path="*"/>
    <add verb="GET,HEAD,POST" path="*" type="Microsoft.SharePoint.ApplicationRuntime.SPHttpHandler, ....."/>
    <add verb="OPTIONS,PROPFIND,PUT,LOCK,UNLOCK,MOVE,COPY,GETLIB,PROPPATCH,MKCOL,DELETE,(GETSOURCE),....."/>
    <add verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.Http....."/>
    <add verb="*" path="_vti_bin/ReportServer" type="Microsoft.ReportingServices.SharePoint.Soap.RSP....."/>
    <add verb="*" path="Reserved.ReportViewerWebPart.axd" type="Microsoft.ReportingServices.SharePoi....."/>
    <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFacto....."/>
    <add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHa....."/>
    <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, ....."/>
    <remove verb="*" path="*.asmx"/>
</httpHandlers>

The <remove verb="*" path="*.asmx"/> key is removing the ScriptHandlerFactory (3 lines above) registration.

Solving is easy, move the <remove verb="*" path="*.asmx"/> key up to the top just below the <remove verb="GET,HEAD,POST" path="*"/> key. In this example your httpHandler section would look like this:

<httpHandlers>
    <remove verb="GET,HEAD,POST" path="*"/>
    <remove verb="*" path="*.asmx"/>            
    <add verb="GET,HEAD,POST" path="*" type="Microsoft.SharePoint.ApplicationRuntime.SPHttpHandler,....."/> 
    <add verb="OPTIONS,PROPFIND,PUT,LOCK,UNLOCK,MOVE,COPY,GETLIB,PROPPATCH,MKCOL,DELETE,(GETSOURCE)....."/> 
    <add verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.Htt....."/> 
    <add verb="*" path="_vti_bin/ReportServer" type="Microsoft.ReportingServices.SharePoint.Soap.RS....."/> 
    <add verb="*" path="Reserved.ReportViewerWebPart.axd" type="Microsoft.ReportingServices.SharePo....."/> 
    <add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFact....."/> 
    <add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptH....."/> 
    <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler,....."/> 
</httpHandlers>

Making changes in the Web.config will cause the application pool to restart, don't do this in a live productional system during working hours, restartig SharePoint takes ages :)

Ever heard about TypeMock?? TypeMock is a tool which simplifies unit testing. As a not proffie unit testing I can tell that TypeMock is pretty easy to learn....

TypeMock has a pretty cool tool now for unit testing SharePoint, it´s called Isolator For SharePoint. It´s the only tool that allows you you unit test your SharePoint application without SharePoint.

I do not have any experience with the tool yet, I´ll keep updates posted on this topic... Did you btw know that you can get a license for free??

Having the problem as well that, when you are testing your ADO.Net Services in Internet Explorer, the browser is not showing anything?

This 'error' occurs when the 'Turn on feed reading view' option is enabled. To disable this, do the following:

Open IE, go to Tools > Internet Options > Content > Feeds (Settings) > Un-tick 'Turn on feed reading view'

Turn on feed reading view Enabled	Turn on feed reading view disabled

I love to check out somebody else his or her code. I always learn something from it. Just a couple of days ago I had an example from Scott Allen about WWF and ASP.Net.

In his code example I found a class with different small data checks. Each static method was decorated with the ´DebuggerStepThroughAttribute´.

public static class Check
{
    [DebuggerStepThrough]
    public static void IsNotNull(object argument, string message)
    {
        if (argument == null)
        {
            throw new InvalidOperationException(message);
        }
    }
}

Not exactly knowing what the attribute meant (besides what the name is telling you) triggered me to ask it Google :)

By placing System.Diagnostics.DebuggerStepThrough attribute above a method, you instruct the debugger to step through that method and not into it. With other words this instruction will cause the debugger not to step into method as normal, but you can always place a breakpoint in that method and stop there.

Hmm sweet isn't it :) Hopefully it's useful for you as well.