Overflow Error: Visual Web Developer

I am using Visual Web Developer to design an interface to query an Access Database. Everything seems to work fine, but when I select the most intensive option I recieve the following error. As I said, everything seems to work fine, unless the user selects all the options I have made available. How do I resolve this issue without limiting the user?

Overflow

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.Data.OleDb.OleDbException: Overflow

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:

[OleDbException (0x80040e57): Overflow] System.Data.OleDb.OleDbCommand.ExecuteCommandTextForSingleResult(tagDBPARAMS dbParams, Object& executeResult) +177 System.Data.OleDb.OleDbCommand.ExecuteCommandText(Object& executeResult) +194 System.Data.OleDb.OleDbCommand.ExecuteCommand(CommandBehavior behavior, Object& executeResult) +56 System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior behavior, String method) +105 System.Data.OleDb.OleDbCommand.ExecuteReader(CommandBehavior behavior) +91 System.Data.OleDb.OleDbCommand.System.Data.IDbCommand.ExecuteReader(CommandBehavior behavior) +4 System.Data.Common.DbDataAdapter.FillInternal(DataSet dataset, DataTable[] datatables, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) +139 System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) +140 System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, String srcTable) +83 System.Web.UI.WebControls.SqlDataSourceView.ExecuteSelect(DataSourceSelectArguments arguments) +1659 System.Web.UI.WebControls.AccessDataSourceView.ExecuteSelect(DataSourceSelectArguments arguments) +58 System.Web.UI.DataSourceView.Select(DataSourceSelectArguments arguments, DataSourceViewSelectCallback callback) +13 System.Web.UI.WebControls.DataBoundControl.PerformSelect() +140 System.Web.UI.WebControls.BaseDataBoundControl.DataBind() +68 System.Web.UI.WebControls.GridView.DataBind() +5 System.Web.UI.WebControls.BaseDataBoundControl.EnsureDataBound() +61 System.Web.UI.WebControls.CompositeDataBoundControl.CreateChildControls() +67 System.Web.UI.Control.EnsureChildControls() +97 System.Web.UI.Control.PreRenderRecursiveInternal() +50 System.Web.UI.Control.PreRenderRecursiveInternal() +171 System.Web.UI.Control.PreRenderRecursiveInternal() +171 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5729

I can post my code as well. It's three group bys, two sums divided by one another on a 30mb Access Database.

Thanks!

It seems like this would be better posted to an Access or ASP.NET forum.