Hi,

We are using Twitterizer for Twitter integration to get the Tweets details. When making call to the method OAuthUtility.GetRequestToken, following exception is coming.

System.Security.SecurityException: Request for the permission of type 'System.Net.WebPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

When the application is hosted on IIS 5, the application works fine and the above error is coming only when the application is hosted in IIS 7 on Windows 2008 R2. and the method OAuthUtility.GetRequestToken throws above exception. It seems the issue is something with code access security. Please suggest what kind of permissions should be given to fix the security exception. The application has the Full Trust and I have even tried by registering the Twitterizer DLL in GAC and still the same error is coming. I am not sure what makes the difference between IIS 5 and IIS 7 with regards to code access security to cause that exception.

Following is the stack track of the exception.

[SecurityException: Request for the permission of type 'System.Net.WebPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.]
   System.Security.CodeAccessSecurityEngine.Check(Object demand, StackCrawlMark& stackMark, Boolean isPermSet) +0
   System.Security.CodeAccessPermission.Demand() +54
   Twitterizer.OAuthUtility.ExecuteRequest(String baseUrl, Dictionary`2 parameters, HTTPVerb verb, String consumerKey, String consumerSecret, String token, String tokenSecret, WebProxy proxy) +224
   Twitterizer.OAuthUtility.GetRequestToken(String consumerKey, String consumerSecret, String callbackAddress, WebProxy proxy) +238
   Twitter._Default.btnSubmit_Click(Object sender, EventArgs e) +94
   System.Web.UI.WebControls.Button.OnClick(EventArgs e) +115
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +140
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +29
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +11045655
   System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +11045194
   System.Web.UI.Page.ProcessRequest() +91
   System.Web.UI.Page.ProcessRequest(HttpContext context) +240
   ASP.authorization_aspx.ProcessRequest(HttpContext context) in c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\twitter\c2fd5853\dcb96ae9\App_Web_y_ada-ix.0.cs:0
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +599
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +171

Any help would be greatly appreciated.

Thanks in advance.

Regards, Raghu