"Conversion Failed When Converting Date And/Or Time From Character String" ? What Can I Do ?

con = new SqlConnection(cs.DBConn);
con.Open();
cmd = new SqlCommand("SELECT RTRIM(invoiceNo) as [Order No],RTRIM(InvoiceDate) as [Order Date],RTRIM(Invoice_Info.CustomerID) as [Customer ID],RTRIM(CustomerName) as [Customer Name],RTRIM(SubTotal) as [SubTotal],RTRIM(VATPer) as [Vat+ST %],RTRIM(VATAmount) as [VAT+ST Amount],RTRIM(DiscountPer) as [Discount %],RTRIM(DiscountAmount) as [Discount Amount],RTRIM(GrandTotal) as [Grand Total],RTRIM(TotalPayment) as [Total Payment],RTRIM(PaymentDue) as [Payment Due],RTRIM(PaymentType) as [Payment Type],RTRIM(Status) as [Status],Remarks from Invoice_Info,Customer where Invoice_Info.CustomerID=Customer.CustomerID and InvoiceDate between @d1 and @d2 order by InvoiceDate desc", con);
cmd.Parameters.Add("@d1", SqlDbType.DateTime, 30, "InvoiceDate").Value = dtpInvoiceDateFrom.Value.Date.ToShortDateString();
cmd.Parameters.Add("@d2", SqlDbType.DateTime, 30, "InvoiceDate").Value = dtpInvoiceDateTo.Value.Date.ToShortDateString();
SqlDataAdapter myDA = new SqlDataAdapter(cmd);
POS_DBDataSet myDataSet = new POS_DBDataSet(); 
myDA.Fill(myDataSet, "Invoice_Info");