Problems setting up ASP.NET 4.0 web on IIS 7


I was attempting to set up a new ASP.NET 4.0 web on my dev machine, running Windows 7 and IIS 7. I ran into several errors, that I suspect others may encounter, and I had to search all over the web to find all the answers. So I’ve written this post in the hopes it saves some other dev the same headache I had!

So, first I created the new website and app pool identity, but when I hit the site for the first time, I got the following error:
HTTP Error 500.19 – Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.

After searching for solutions, I found most had to do with permissions to the web.config file or actual locking of sections of the web.config file. I confirmed that the app pool identity had permissions to the file, and there were no locking attributes in the file. So something else had to be the issue. Then I found this post:
It turns out that ASP.NET had not been configured fully on my machine. So, according to one of the answers on the post, the solution is to do the following steps:
1. Open control panel
2. Click on “Programs and Features”
3. Click on ”Turn windows features on/off”
4. Locate ”Internet Information services IIS” in the pop up window and expand its node
5. Expand the ”World Wide Web Service” node
6. Expand “Application Development Features” node
7. Check the check box of”ASP.NET”
8. Then click ok button
9. You will need to restart your computer (go get a cup of coffee…)

After restarting, and hitting the site again, I got this new error:
HTTP Error 500.21 – Internal Server Error
Handler “PageHandlerFactory-Integrated” has a bad module “ManagedPipelineHandler” in its module list
Another web search revealed that even though the step above enabled ASP.NET, it was not fully installed. This article shows how to finish the installation:
Basically, just open a command window and enter the command shown below (command is slightly different for 32-bit vs. 64-bit).
%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe -i

32 bit:
%windir%\Microsoft.NET\Framework\v4.0.21006\aspnet_regiis.exe -i

If you get a permissions error, you need to run the window as an administrator. To do this, go to start |run, and type ‘cmd’, but hit Ctrl-Shift-Enter, instead of just Enter.
After doing that, I hit the site again, and it worked! Hope this has helped!



A recent posting to a technical mailing list I’m on asked how to pass a parameter to a button click-event handler. The programmer wanted to do the equivalent of this:

<asp:button ID="btnSubmit" runat="server" OnClick="Btn_Onclick(PARAM)" />

But, she knew this didn’t work, because the default signature of event handlers in ASP.NET is this:

void myBtn_OnClick(Object sender, EventArgs e)

So, she was stumped on how to pass some sort of argument to the event handler.

Now, there a certainly some kludges that would work, such as having a hidden form field which contains the ‘parameter’ value, and having the event-handler get the value that way. But surely, there’s a better way? Well, yes, of course there is! :)

This better way is to use the “CommandArgument” property on the button control. This property is directly accessable in the event handler. The added bonus is that you can write a single even-handler for all of your button clicks, and use the associated “CommandName” property to know which button fired.

So, now, in your aspx page, your button object will be declared thusly:

<asp:Button ID="test" runat="server" CommandArgument="MyVal" CommandName="ThisBtnClick" OnClick="MyBtnHandler" />

Then, in the OnClick handler, you can cast the sender object to the correct type, and get the values of
CommandName & CommandArgument. (You could make this even more generic and handle the OnClick event for different senders, but we’ll leave that for a later post! :)

void MyBtnHandler(Object sender, EventArgs e)
	 Button btn = (Button)sender;
          switch (btn.CommandName)
                case "ThisBtnClick":
                case "ThatBtnClick":

You can see that the switch statement uses the CommandName property to determine which button was clicked, and then can use the CommandArgument property passed in by the button click event.

Voila! You’ve “passed a parameter” to a button click-event handler!

[UPDATE] Thanks to Jim for pointing out some confusion in my sample code. I hope that this version is clearer.