Mail sending

Question

hello sir..

i devlop one site..
in this when i send mail through my applicaion mail send successfully..
but
when i upload my site in server..and i try to send e-mail the error occured..

Server Error in '/' Application.

---

Security Exception

Description: The application attempted to perform an operation not allowed by the security policy.  To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file.

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

Source Error:

[No relevant source lines]

Source File: App_Web_mr0ziacg.1.cs   Line: 0

Stack Trace:

[SecurityException: Request for the permission of type 'System.Net.Mail.SmtpPermission, 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() +58 System.Net.Mail.SmtpClient.Initialize() +128 System.Net.Mail.SmtpClient..ctor(String host, Int32 port) +220 Inquiry.btnadd_Click(Object sender, EventArgs e) +589 System.EventHandler.Invoke(Object sender, EventArgs e) +0 System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +110 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +6785 System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +242 System.Web.UI.Page.ProcessRequest() +80 System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) +21 System.Web.UI.Page.ProcessRequest(HttpContext context) +49 ASP.inquiry_aspx.ProcessRequest(HttpContext context) in App_Web_mr0ziacg.1.cs:0 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +181 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75

---

Version Information: Microsoft .NET Framework Version:2.0.50727.3625; ASP.NET Version:2.0.50727.3634