Security exception while opening an OleDBConnection

[CyberLotus]

Hi,

I've created a web application and through this I want to import Excel data
to database.
Following is the code that I've written,

************************************************** *****************
string fileLocation = txtboxFileName.Text.ToString();
string sheetName = "Import";
string connectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data
Source="+fileLocation+";Extended Properties=Excel 8.0";
string strSQL = "select * from ["+sheetName+"$]";

OleDbConnection cn = new OleDbConnection(connectionString); // It's failing
here

cn.Open();
OleDbCommand cm = new OleDbCommand(strSQL,cn);
OleDbDataAdapter da = new OleDbDataAdapter(cm);
DataSet excelDS = new DataSet();
da.Fill(excelDS);
......................
......................
......................
************************************************** *****************

I've used OleDBConnection for reading the excel, but it's giving me a
Security Exception.
Here's the exception:

################################################## ##################
Server Error in '/PreSa' 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 failed.

Source Error:

An unhandled exception was generated during the execution of the current web
request. Information regarding the origin and location of the exception can
be identified using the exception stack trace below.

Stack Trace:

[SecurityException: Request failed.]
Try2.WebUserControl2.btnSend_Click(Object sender, EventArgs e) +0
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +108

System.Web.UI.WebControls.Button.System.Web.UI.IPo stBackEventHandler.RaisePostBackEvent(String eventArgument) +57
System.Web.UI.Page.RaisePostBackEvent(IPostBackEve ntHandler
sourceControl, String eventArgument) +18
System.Web.UI.Page.RaisePostBackEvent(NameValueCol lection postData) +33
System.Web.UI.Page.ProcessRequestMain() +2112
System.Web.UI.Page.ProcessRequest() +217
System.Web.UI.Page.ProcessRequest(HttpContext context) +18

System.Web.CallHandlerExecutionStep.System.Web.Htt pApplication+IExecutionStep.Execute() +179
System.Web.HttpApplication.ExecuteStep(IExecutionS tep step, Boolean&
completedSynchronously) +87


--------------------------------------------------------------------------------
Version Information: Microsoft .NET Framework Version:1.1.4322.2300; ASP.NET
Version:1.1.4322.2300

################################################## ##################

Please help me as it's very urgent.

Thanks a ton.
Regards,
Lotus