I have a gridview that has a couple of Label server controls nested inside an ItemTemplate. I want to assign their Text value when each row is databound (I'm using Profile properties so I have to get the user and their profile to get the values).

<asp:GridView ID="grdUsers" runat="server" AllowPaging="True" AutoGenerateColumns="False" DataKeyNames="UserName,UserID" DataMember="DefaultView" DataSourceID="dsUsers" EmptyDataText="There are no users">
                        <asp:HyperLinkField DataTextField="UserName" DataNavigateUrlFields="UserName" DataNavigateUrlFormatString="~/AddUser.aspx?UserName={0}"  HeaderText="Login Name" />
                                <asp:Label ID="lblLastName" runat="server"></asp:Label>
                                <asp:Label ID="lblFirstName" runat="server"></asp:Label>
                        <asp:CheckBoxField DataField="AdminRole" HeaderText="Admin" />
                        <asp:CheckBoxField DataField="AdminUsersRole" HeaderText="AdminUser" />
                        <asp:CheckBoxField DataField="ChangeProfileRole" HeaderText="Prof" />
                        <asp:CheckBoxField DataField="CreateAccountRole" HeaderText="Add" />
                        <asp:CheckBoxField DataField="DeleteAccountRole" HeaderText="Del" />
                        <asp:CheckBoxField DataField="EmulationRole" HeaderText="Emul" />
                        <asp:CheckBoxField DataField="ViewStatsRole" HeaderText="Stat" />
                        <asp:CheckBoxField DataField="VoidCheckRole" HeaderText="Void" />

I'm using the gridview's RowDataBound event to do the label.Text assignment

protected void grdUsers_RowDataBound(object sender, GridViewRowEventArgs e)
        if (e.Row.RowType == DataControlRowType.DataRow)
            memUser = Membership.GetUser(Convert.ToString(DataBinder.Eval(e.Row.DataItem, "UserName")));
            userProfile = Profile.GetProfile(memUser.UserName);

            Label lastName = (Label)grdUsers.FindControl("lblLastName");
            Label firstName = (Label)grdUsers.FindControl("lblFirstName");
            lastName.Text = userProfile.LastName;
            firstName.Text = userProfile.FirstName;

It's failing and giving me an error message stating that lastName is null. What am I doing wrong here? Any and all assistance is much appreciated. Thanks in advance.

You need to bind the labels text to some field value like Text='<%#Bind(ColumnName) %>'

Since you are not binding i suppose you are getting the error for null values in

Another thought:
Do you allow NULL value in your database for LastName field?
If yes then you need to handle tat NULL in your code.