Could Not Load File or Assembly Sharepoint 2007 WebPart

Question

I am playing around with Sharepoint 2007. I have a virtual machine (win server 2k3) with an instance of sharepoint server 2007 running on it. I am now working on creating web parts. I have successfully created simple ones, such as this one that displays text:

public class SimpleWebPart : WebPart
{
    private string _displayText = "Hello World!";
    [WebBrowsable(true), Personalizable(true)]
    public string DisplayText
    {
        get { return _displayText; }
        set { _displayText = value; }
    }
    protected override void Render(System.Web.UI.HtmlTextWriter writer)
    {
        writer.Write(_displayText);
    }
}

I have this one (and a few test ones) inside of a Class Library, which I put into the _app_bin folder inside of C:\Inetpub\wwwroot\wss\VirtualDirectories\80.

The latest one I added utilizes LINQ to get data from a table I added (not part of Sharepoint):

public class SimpleDBWebPart : WebPart
{
    protected override void Render(System.Web.UI.HtmlTextWriter writer)
    {
        var oDB = new SPWebPartDataClassesDataContext();
        var oRes = oDB.GetAllFirstTable();

        foreach(var item in oRes)
        {
            writer.Write("<div>Item Name: {0}</div>",item.text);
            writer.Write("<div>Item ID: {0}</div>", item.id);
        }
    }
}

The GetAllFirstTable() is a stored procedure that gets all the data from my test table:

ALTER PROCEDURE dbo.GetAllFirstTable
AS
    SELECT * FROM FirstTable
    RETURN

When I try to add the WebPart to a page, I get this error:

The "SimpleDBWebPart" Web Part appears to be causing a problem. Could not load file or assembly 'System.Data.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.

I used Reflector to make sure I have the assembly inside the DLL: alt text

And that appears to be the case. Do I have to add the assembly to the web.config file of the sharepoint site? Or is there something else that I am missing?

Thanks guys!

Kusek Kusek · Accepted Answer · 2009-08-05T17:35:27

To use LINQ or .NET 3.5 feature you need to first configure the SharePoint to run in 3.5 Mode. Refer to these links on how to do that

Simplest way

AnotherOne

Could Not Load File or Assembly Sharepoint 2007 WebPart

1 Answers