How to set the table cell visible property in code.

I set the visible property of a table cell to false.

I can set the property to true in the Page_Load procedure.

The property is not set in any other procedure.

ASPX file
=======
<asp:TableCell ID="celMenu"  Visible="False">

Code Behind

protected void Page_Load(object sender, EventArgs e)
        {
            celMenu.Visible = true;  // celMenu becomes visible
            if (!IsPostBack)
            {
                StockProLogin.Focus();
                //mnuScoreStocks.Visible = false;
                celMenu.Visible = true;   // celMenu becomes visible
               
            }
        }


            if (currentUser != null) // User is in database
            // Determine user status
            {

                // Verify registration status
                strUserName = currentUser.UserName;
                strUserID = currentUser.ProviderUserKey.ToString();
                e.Authenticated = (strUserName == "dovberman");
 
                if (e.Authenticated==true)
                {
                    strUserName = StockProLogin.UserName;
                    strUserID = currentUser.ProviderUserKey.ToString();
                    string strLoginText = "Hi " + StockProLogin.UserName + " You are logged in";
                    lblLoginMsg.Text = strLoginText;
                    // lblLoginMsg. Text displays as expected.
                    celMenu.Visible = true;  // celMenu does not become visible
                }

                else // User is not in database
                {
                    e.Authenticated = false;
                    StockProLogin.FailureText = StockProLogin.UserName + ". You were not found. Re-enter User Name and or Password.";
// StockProLogin.FailureText  displays as expected.
                    celMenu.Visible = false;
                }
                            }

Please help.

Thanks