Edit button not working on datalist causes invalid postback - asp.net

Question

I have a datalist and a binddata Sub in vb side that works on page load and I can see all my data but then when I click edit it brings up this error:-
Invalid postback or callback argument. Event validation is enabled using in configuration or <%# Page EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.
Here is My vb code:-
Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
BindData()
End Sub
Protected Sub BindData()
Dim cn As SqlConnection = New SqlConnection()
Dim cmd As SqlCommand = New SqlCommand()
cn.ConnectionString = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
cmd.Connection = cn
cmd.CommandText = "SELECT DISTINCT Users.User_ID, Users.FirstName, Users.LastName, Users.Password, Users.Email, Users.ContactNum, Users.Address, Users.County, Users.Gender, Users.Datejoined, Users.Dateleft, Users.Subscription_ID, Subscriptions.Subscription_type FROM Users INNER JOIN Subscriptions ON Users.Subscription_ID = Subscriptions.Subscription_ID WHERE (Users.Dateleft IS NULL)"
cn.Open()
Dim ds As SqlDataReader
ds = cmd.ExecuteReader()
MyDataList.DataSource = ds
MyDataList.DataBind()
cn.Close()
End Sub
Sub myDataList_EditCommand(sender As Object, e As DataListCommandEventArgs) Handles MyDataList.EditCommand
BindData()
MyDataList.EditItemIndex = e.Item.ItemIndex
End Sub
And this is my asp.net :-
<asp:DataList ID="MyDataList"
runat="server"
RepeatColumns="2" CellSpacing="-1" Font-Bold="False" Font-Italic="False"
Font-Names="Arial" Font-Overline="False" Font-Size="Medium"
Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center"
ShowFooter="False" ShowHeader="False"
onItemDataBound="myDataList_ItemDataBound"
onEditCommand="myDataList_EditCommand"
onCancelCommand="myDataList_CancelCommand"
onUpdateCommand="myDataList_UpdateCommand"
onDeleteCommand="myDataList_DeleteCommand"
RepeatDirection="Horizontal">
<ItemStyle Font-Bold="False" Font-Italic="False" Font-Overline="False"
Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center"
VerticalAlign="Middle" />
<ItemTemplate>
<br />
<div style="padding:15,15,15,15;font-size:10pt;font-family:Verdana">
<table class="style1">
<tr>
<td class="style2">
User ID</td>
<td>
<asp:Label ID="lblID" runat="server" Text='<%# Eval("User_ID") %>' />
</td>
</tr>
<tr>
<td class="style2">
Details</td>
<td>
<i><b>
<asp:Label ID="lblFName" runat="server" Text='<%# Eval("FirstName") %>' />
<asp:Label ID="lblLName" runat="server" Text='<%# Eval("LastName") %>' />
</i></b>
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:Label ID="Address" runat="server" Text='<%# Eval("Address") %>' />
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:Label ID="lblCounty" runat="server" Text='<%# Eval("County") %>' />
</td>
</tr>
<tr>
<td class="style2">
Contact Details</td>
<td>
<asp:Label ID="lblEmail" runat="server" Text='<%# Eval("Email") %>' />
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:Label ID="lblNum" runat="server" Text='<%# Eval("ContactNum") %>' />
</td>
</tr>
<tr>
<td class="style2">
Package ID</td>
<td>
<asp:Label ID="lblSub" runat="server" Text='<%# Eval("Subscription_ID") %>' />
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:Label ID="lblDes" runat="server" Text='<%# Eval("Subscription_type") %>' />
</td>
</tr>
<tr>
<td class="align-center" colspan="2">
<asp:Button ID="btnEdit" runat="server" CommandName="Edit" Text="Edit" />
<asp:Button ID="btnDelete" runat="server" CommandName="Delete" Text="Delete" />
</td>
</tr>
</table></div>
<br />
</ItemTemplate>
<EditItemTemplate>
<table class="style1">
<tr>
<td class="style2">
User ID</td>
<td>
<asp:Label ID="lblID" runat="server" Text='<%# Eval("User_ID") %>' />
</td>
</tr>
<tr>
<td class="style2">
Details</td>
<td>
<asp:TextBox ID="txtFName" runat="server" text='<%#Container.DataItem("FirstName")%>'></asp:TextBox>
<asp:TextBox ID="txtLName" runat="server" text='<%#Container.DataItem("LastName")%>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="style3">
</td>
<td class="style4">
<asp:TextBox ID="lblAdd" runat="server"
text='<%#Container.DataItem("Address")%>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:TextBox ID="lblCounty" runat="server"
text='<%#Container.DataItem("County")%>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="style2">
Contact Details</td>
<td>
<asp:TextBox ID="lblEmail" runat="server"
text='<%#Container.DataItem("Email")%>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:TextBox ID="lblNum" runat="server"
text='<%#Container.DataItem("ContactNum")%>'></asp:TextBox>
</td>
</tr>
<tr>
<td class="style2">
Package ID</td>
<td>
<asp:Label ID="lblSub" runat="server" Text='<%# Eval("Subscription_ID") %>' />
</td>
</tr>
<tr>
<td class="style2">
</td>
<td>
<asp:Label ID="lblDes" runat="server" Text='<%# Eval("Subscription_type") %>' />
</td>
</tr>
<tr>
<td class="align-center" colspan="2">
<asp:LinkButton ID="lnkUpdate" runat="server" CommandName="Update">Update</asp:LinkButton>
<asp:LinkButton ID="lnkCancel" runat="server" CommandName="Cancel">Cancel</asp:LinkButton>
</td>
</tr>
</table>
</EditItemTemplate><SelectedItemStyle Font-Bold="False" Font-Italic="False" Font-Overline="False"
Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center"
VerticalAlign="Middle" />
I have put Page EnableEventValidation="false" but that just does nothing, i dont tell the error but nothing happens.
Please help me.

Answer 1

Try changing the following code:
Sub myDataList_EditCommand(sender As Object, e As DataListCommandEventArgs) Handles MyDataList.EditCommand
BindData()
MyDataList.EditItemIndex = e.Item.ItemIndex
End Sub
to this
Sub myDataList_EditCommand(sender As Object, e As DataListCommandEventArgs) Handles MyDataList.EditCommand
MyDataList.EditItemIndex = e.Item.ItemIndex
MyDataList.DataBind()
End Sub