Question

I’m working on a .NET 2.0 C# project using the Newtonsoft.JSON library. When i check the web.config file all assemblies refer to the 2.0 version.

However when i deploy on the server i get the following error :

    Could not load file or assembly 'System.Core, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.IO.FileNotFoundException: Could not load file or assembly 'System.Core, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.

Source Error:


Line 21:     }
Line 22: 
Line 23:     Dictionary<string, string> config = JavaScriptConvert.DeserializeObject<Dictionary<string, string>>(jason);
Line 24: 
Line 25:     if (Request.Form["login"] == config["adminLogin"] && FormsAuthentication.HashPasswordForStoringInConfigFile(Request.Form["password"], "sha1") == config["adminPass"])


Source File: c:\Website\WSRecrut\Test\ConnectionPost.aspx    Line: 23

Assembly Load Trace: The following information can be helpful to determine why the assembly 'System.Core, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' could not be loaded.


WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].


Stack Trace:


[FileNotFoundException: Could not load file or assembly 'System.Core, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.]
   Newtonsoft.Json.Utilities.CollectionUtils.CreateDictionaryWrapper(Object dictionary) in D:\Newtonsoft\Projects\Json\trunk\Src\Newtonsoft.Json\Utilities\CollectionUtils.cs:422
   Newtonsoft.Json.JsonSerializer.CreateObject(JsonReader reader, Type objectType, Object existingValue) in D:\Newtonsoft\Projects\Json\trunk\Src\Newtonsoft.Json\JsonSerializer.cs:223
   Newtonsoft.Json.JsonSerializer.Deserialize(JsonReader reader, Type objectType) in D:\Newtonsoft\Projects\Json\trunk\Src\Newtonsoft.Json\JsonSerializer.cs:169
   Newtonsoft.Json.JavaScriptConvert.DeserializeObject(String value, Type type, JsonConverter[] converters) in D:\Newtonsoft\Projects\Json\trunk\Src\Newtonsoft.Json\JavaScriptConvert.cs:512
   Newtonsoft.Json.JavaScriptConvert.DeserializeObject(String value, JsonConverter[] converters) in D:\Newtonsoft\Projects\Json\trunk\Src\Newtonsoft.Json\JavaScriptConvert.cs:485
   Newtonsoft.Json.JavaScriptConvert.DeserializeObject(String value) in D:\Newtonsoft\Projects\Json\trunk\Src\Newtonsoft.Json\JavaScriptConvert.cs:457
   ASP.connectionpost_aspx.__Render__control1(HtmlTextWriter __w, Control parameterContainer) in c:\Website\WSRecrut\Test\ConnectionPost.aspx:23
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +2113547
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +24
   System.Web.UI.Page.Render(HtmlTextWriter writer) +26
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1896

Does anybody have an idea ? Where can that assembly on 3.5 could come from ?

Answer 1

I suspect you’ve included the wrong NewtonSoft.Json.dll library. There’s multiple assemblies – only one of which supports .NET 2.0.

If you have Reflector/JustDecompile, you can verify that it has an internal class Newtonsoft.Json.Utilities.LinqBridge – that’s what allows it to get away with not using the System.Core LINQ methods.

The File Details also have .NET 2.0 in the description.