I am receiving: Element "ScriptManager" is not a known element. This can occur if there is a compilation error in the website. This happens when I add any AJAX component to my application. When I press F5, I then receive: Unknown server tag 'asp:ScriptManager.' I am unable to use any AJAX componetns.

I am following the Microsoft video

Video - Developing ASP.NET 2.0 Applications using AJAX

by Scott Guthrie

Any suggestions?

Thank you,

deDogs.

If you want to run Ajax website in visual studio,you need to download Ajax Beta 2 or Futures Nov CTP from here - http://ajax.asp.net/default.aspx?tabid=47&subtabid=471 first and install them in your PC.Besides,if you need to refer to Ajax controls,you have to add reference to AjaxControlToolkit.dll. Try to download it from here - http://www.codeplex.com/AtlasControlToolkit
Wish the above can help you get started with Ajax.

Hello,

I had ajax already installed. The ajax extensions are visible in the toolbar. However, I unistalled ajax, and downloaded and installed a  fresh copy. The ajax extensions are visible in the toolbar, however, when I add, lets say, a ScriptManager (<asp:ScriptManager id="s1" enablepartialrendering="true" runat="server">) to the page. The sqiggly line is displayed below ScriptManager, and when I mouse hover over the sqiggly, the context menu displays: Element "ScriptManager" is not a known element. This can occur if there is a compilation error in the Web site.

This is not specific to only ScriptManager, it includes all the ajax extension that I receive this error.
 <asp:Timer runat="server">,<asp:UpdatePanel runat="server">, etc.

I am using Visual Web Developer 2005 Express Edition.

Any ideas,

deDogs

deDogs ...

That's a known issue. It should be fine when you run you app. It's the same on my machine. Sometimes it goes away when  your masterpage (where you put your scriptmanager) is opened.

 

WS

 

 

Yes.This is a known issue when you use ajax controls in master page and content page based on Ajax Beta 2 framework.But you can run 
your website fine.Just as WS said,sometimes it went away when your master page or content page is opened.Wish this issue would be resolved in Ajax next release.

I had a similar problem that was caused primarily by my own lack of knowledge.  I hadn't told the page that I was using AJAX Extensions...so I added to the web.config and my application was brought back to the land of the living.

 

<pages>

     <controls>

              <add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>

      </controls>

</pages>

Thanks, MReynolds for  the tip.  That helps me greatly.

 

I also have the same problem, my situation was, I wasn't using masterpages but just plain aspx form. I also have installed latest AjaxToolkit dll's... any idea guys? need your help... thanks.

I dont see <pages> in my web.config. I do see 

<pages enableSessionState="false" enableViewState="true" enableViewStateMac="true" validateRequest="false" pageParserFilterType="Microsoft.SharePoint.ApplicationRuntime.SPPageParserFilter, Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" asyncTimeout="7">
     .......  

</pages>

 So should I copy your lines in between <pages enableSessionState ............ </pages> ?

Thanks

 

This falls within the configuration tag.

<system.web>

<pages>

<controls>

<add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>

</controls>

</pages>

</system.web>

 

 Hi

Following are some tips to make sure asp.net ajax framework is properly installed :-

1.) Check out for the following folder/directory in your system :- %system root%/program files/Microsoft Asp.net . (This folder contains the dlls  required for asp.net ajax framework functionality).

2.) Once asp.net ajax framework is properly installed open VS2005 (incase u r using it , VS2008 already comes with ajax framework ) -> choose web site -> there you can see option "asp.net ajax enabled website" option.

3.) Now if you want to migrate your existing application to asp.net ajax enabled application , do the following :-

i) add the dlls to your application bin folder .

ii) For modification of web config file the best way is to create a dummy web site by choosing "asp.net ajax enabled website" option and then copying the missing portions from this webconfig to your application webconfig file .

4.) AjaxControlToolkit dll are simply added to your application bin folder , no installation is required as such . Make sure you download proper binaries corresponding to your .net framework installed in your system .