try changing if condition like below
if (
(Request.QueryString["Fullname"] != null && !string.IsNullOrEmpty(Request.QueryString["Fullname"].ToString()))
||
(Request.QueryString["RecordNumber"] != null && !string.IsNullOrEmpty(Request.QueryString["RecordNumber"].ToString()))
||
(Request.QueryString["EmpEmail"] != null && !string.IsNullOrEmpty(Request.QueryString["EmpEmail"].ToString()))
||
(Request.QueryString["Date"] != null && !string.IsNullOrEmpty(Request.QueryString["Date"].ToString()))
||
(Request.QueryString["SlotID"] != null && !string.IsNullOrEmpty(Request.QueryString["SlotID"].ToString()))
||
(Request.QueryString["Timeslot"] != null && !string.IsNullOrEmpty(Request.QueryString["Timeslot"].ToString()))
)
{
}
i try with this and its working fine.
test.aspx?Fullname=test&RecordNumber=5&Date=12102010&SlotID=5&Timeslot=5&EmpEmail=test