asp.net: Invalid postback or callback argument

Question

I am getting this error:

Server Error in '/' Application.

Invalid postback or callback argument.  Event validation is enabled using <pages enableEventValidation="true"/> 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.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.ArgumentException: Invalid postback or callback argument.  Event validation is enabled using <pages enableEventValidation="true"/> 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.

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 


[ArgumentException: Invalid postback or callback argument.  Event validation is enabled using <pages enableEventValidation="true"/> 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.]
   System.Web.UI.ClientScriptManager.ValidateEvent(String uniqueId, String argument) +8627417
   System.Web.UI.WebControls.ListBox.LoadPostData(String postDataKey, NameValueCollection postCollection) +360
   System.Web.UI.WebControls.ListBox.System.Web.UI.IPostBackDataHandler.LoadPostData(String postDataKey, NameValueCollection postCollection) +13
   System.Web.UI.Page.ProcessPostData(NameValueCollection postData, Boolean fBeforeLoad) +346
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1743

Version Information: Microsoft .NET Framework Version:2.0.50727.3623; ASP.NET Version:2.0.50727.3618

What does it mean?

Here is my code:

<%@ Page EnableEventValidation="true" Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="EnterData.DataEntry.WebForm1" %>    

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title></title>

    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.min.js" type="text/javascript"></script>
    <script src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.16/jquery-ui.js" type="text/javascript"></script>

    <link href="../niceforms/niceforms-default.css" rel="stylesheet" type="text/css" />
    <script src="../niceforms/niceforms.js" type="text/javascript"></script>

    <link href="../jquery-ui-1.8.16.custom.css" rel="stylesheet" type="text/css" />
    <style type="text/css">
        .list-problems {
        height:600px !important;
        width:200px !important;
        display:inline-block;
    }
    </style>

    <script>
        jQuery(function($) {
        //$("#occurrence_dateTextBox").mask("99/99/9999");
        //$("#<%= report_dateTextBox.ClientID %>").mask("99/99/9999");
        $("#<%= occurrence_dateTextBox.ClientID %>").datepicker();
        $("#<%= report_dateTextBox.ClientID %>").datepicker();
        //$(".datepicker").datepicker(); 

    });
    $(function() {
        $.get('../file.txt', function(data) {
            var output = data.split('\n'),
            tmp = '';
            for (i = 0; i < output.length; i++) {
                tmp += '<option value=' + output[i] + '>' + output[i] + '</option>';
            }
            $('#lstProblems').html(tmp);

        });
    });

    $(function() {
        $("select").multiselect();
    });

    function getselectedproblems() {
        var selectedLanguages = new Array();
        jQuery('#lstProblems option:selected').each(function() {
            selectedLanguages.push(jQuery(this).val());
        });
    }

    </script>

</head>
<body><div id="container">
    <form id="form1" runat="server" class="niceform">

        <fieldset>

        <legend>Section A</legend>

        <dl>

            <dt><label for="occurrence_dateTextBox" >Occurrence Date:</label></dt>
            <dd><asp:TextBox ID="occurrence_dateTextBox" runat="server" size="50"/></dd>
        </dl>

        <dl>

            <dt><label for="report_dateTextBox">Report Date:</label></dt>
            <dd><asp:TextBox ID="report_dateTextBox" runat="server" size="50"/></dd>
        </dl>

        <dl>

            <dt><label for="spec_idTextBox">Specimen ID:</label></dt>
            <dd><asp:TextBox ID="spec_idTextBox" runat="server" size="50"/></dd>
        </dl>

        <dl>

            <dt><label for="batch_idTextBox">Batch ID:</label></dt>
            <dd><asp:TextBox ID="batch_idTextBox" runat="server" size="50"/></dd>
        </dl>

        <dl>

            <dt><label for="report_byTextBox">Report By:</label></dt>
            <dd><asp:TextBox ID="report_byTextBox" runat="server" size="50"/></dd>
        </dl>

        <dl>

            <dt><label for="identified_byTextBox">Identified ID:</label></dt>
            <dd><asp:TextBox ID="identified_byTextBox" runat="server" size="50"/></dd>
        </dl>

        </fieldset>

        <fieldset>
        <legend>Section B</legend>

        <dl>

            <dt><label for="problemTextBox">Problem:</label></dt>
            <dd><asp:TextBox ID="problemTextBox" runat="server" size="50"/></dd>


        </dl>

        <dl>
            <dt><label for="lstProblems">Problems List:</label></dt>
            <dd>
                <asp:ListBox ID="lstProblems" runat="server" SelectionMode="Multiple" CssClass="list-problems"></asp:ListBox>
            </dd>

        </dl>  

        <dl>
                <dd><select size="8" multiple="true" >
                <optgroup label="Europe">
                    <option>United Kingdom</option>
                    <option>Luxembourg</option>
                </optgroup>    
                <optgroup label="Asia">
                    <option>India</option>
                    <option>Dubai</option>
                </optgroup>
            </select> </dd>    
        </dl>
        <dl>
            <asp:ListBox ID="ListBox1" runat="server" DataSourceID="SqlDataSource1" 
                DataTextField="batch" DataValueField="batch" SelectionMode="Multiple" 
                Height="100px" Width="329px"></asp:ListBox>
            <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
                ConnectionString="<%$ ConnectionStrings:LOM %>" 
                SelectCommand="SELECT [batch] FROM [lom_batch]"></asp:SqlDataSource>
        </dl>

        </fieldset>

        <fieldset>
        <legend>Section C</legend>
        <dl>

            <dt><label for="section_c_issue_error_identified_byTextBox">Issue/Error Identified By:</label></dt>
            <dd><asp:TextBox ID="section_c_issue_error_identified_byTextBox" runat="server" size="50"/></dd>


        </dl>

        <dl>

            <dt><label for="section_c_commentsTextBox">Comments:</label></dt>
            <dd><asp:TextBox ID="section_c_commentsTextBox" runat="server" size="50"/></dd>


        </dl>       

        </fieldset>

        <fieldset>
        <legend>Section D</legend>
        <dl>

            <dt><label for="section_d_investigationTextBox">Investigation:</label></dt>
            <dd><asp:TextBox ID="section_d_investigationTextBox" runat="server" size="50"/></dd>


        </dl>

        </fieldset>

        <fieldset>
        <legend>Section E</legend>
        <dl>

            <dt><label for="section_e_corrective_actionTextBox">Corrective Action:</label></dt>
            <dd><asp:TextBox ID="section_e_corrective_actionTextBox" runat="server" height="200" TextMode="MultiLine" size="50"/></dd>


        </dl>


        </fieldset>

        <fieldset>
        <legend>Section F</legend>
        <dl>

            <dt><label for="section_f_commentsTextBox">Comments:</label></dt>
            <dd><asp:TextBox ID="section_f_commentsTextBox" runat="server" size="50"/></dd>


        </dl>

        </fieldset>

        <fieldset>
        <legend>Pre-Analytical</legend>
        <dl>

            <dt><label for="prePracticeCodeTextBox">Practice Code:</label></dt>
            <dd><asp:TextBox ID="prePracticeCodeTextBox" runat="server" Visible="false"/></dd>


        </dl>

        <dl>

            <dt><label for="preContactTextBox1">Contact:</label></dt>

            <dd><asp:TextBox ID="preContactTextBox" runat="server" Visible="false"/></dd>


        </dl>

        <dl>
            <dt><label for="CheckBox1">PreAnalytical?</label></dt>
            <dd> <asp:CheckBox ID="CheckBox1" runat="server" CausesValidation="false"
                            Visible="true" AutoPostBack="true" OnCheckChanged="CheckBox1_CheckedChanged"/></dd>
        </dl>

        </fieldset>

        <asp:Button ID="Button1" runat="server" Text="Button" OnClick="SubmitData"  OnClientClick="JSfunction()"/>

    </form>

</div></body>
</html>

What am I doing wrong?

I am getting this error after I press the submit button.

Royi Namir · Accepted Answer · 2013-07-29T10:46:40.623

72

in you aspx file you should put the first line as this :

<%@ Page EnableEventValidation="false" %>

if you already have something like <%@ Page so just add the rest => EnableEventValidation="false" %>

I recommend not to do it.

edited Jul 29 '13 at 10:46

answered Sep 19 '11 at 19:38

Royi Namir

144,742
138
468
792

1

This answer is backwards, EnableEventValidation="false" is what you mean, I believe. – Dave L Sep 19 '11 at 19:50
@mid7 do you know how i can get this done server side?> (populating the listbox) – Alex Gordon Sep 19 '11 at 21:17
56

Disable eventvalidation (bad idea, because you lose a little of security that come with very little cost). – Nick Kahn May 19 '12 at 02:41
2

this is a very bad idea to do – Alex Jul 29 '13 at 09:42
SHEKHAR - fix it properly. If you disable event validation then something like this can happen: Let's say you have a forum with 3 types of user, member,moderator and admin. I'm a moderator and when I create a user I can pick from member or moderator in a drop down list but not admin because I do not have permission. If you disable event validation then I can just change the value of the drop down list to admin by hand and submit the form. Big security risk! – JoeS Jul 29 '15 at 21:26
Disabling event validation lessens security and is not good practice – Dirk Strauss Oct 14 '15 at 15:19
11

Why would you post something you don't recommend doing? – d512 Sep 17 '16 at 19:49
2

@user1334007 because it is an answer to his question . Ms did supply this to prevent this error. It doesnt mean that i agree . They also added sqldataadapter . Will i agree to use it ? No – Royi Namir Sep 17 '16 at 19:52
@JoeS: For some time if we forget about asp.net webforms & talks about ASP.Net MVC, we can temper the data at browser and post to the server. And for such things, it is always recommend to put server-side validation & authorization. So it's not bad to disable "EnableEventValidation" property. – Jitendra Pancholi Sep 18 '17 at 05:59

score 30 · Answer 2 · edited May 23 '17 at 12:26

30

If you look at the first lines of text you can glean what your error is.

this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them

You're dynamically editing the lstProblems dropdown, so when you post back ASP.NET says "Warning! Invalid entries in the dropdown!" and freaks out throwing that error. You have to determine if turning off event validation is an OK solution, but I would research it before doing it, since the idea behind it is to make your site more secure for free.

Here's another stackoverflow answer that does a much better job explaining what to do than me: Invalid postback or callback argument. Event validation is enabled using '<pages enableEventValidation="true"/>'

edited May 23 '17 at 12:26

Community

1
1

answered Sep 19 '11 at 19:45

Dave L

1,636
9
10

how do i turn off the validation? i am not editing the entries i just add from a data source once and thats it – Alex Gordon Sep 19 '11 at 19:47
The problem is you're adding the values client side. ASP knows that it rendered the dropdown to the page with a certain set of valid values. The value selected by the client was not contained in the original set of values, so it asumes the user hacked the dropdown list to add that value and stops processing the page. – Dave L Sep 19 '11 at 19:58
but the user has no way of adding values into it. why does asp think that he added values? – Alex Gordon Sep 19 '11 at 20:01
1

The user is adding values through javascript: $('#lstProblems').html(tmp); There are several ways through browsers to manipulate the DOM too, like IE Developer Tools, Inspect Element in Chrome, Firebug in Mozilla, etc... – Dave L Sep 19 '11 at 20:02

score 18 · Answer 3 · answered May 20 '14 at 20:41

18

If you have code in your Page_Load() event. Try adding this:

if (!Page.IsPostBack)
{ 
//your code here 
}

answered May 20 '14 at 20:41

Syed Ali Taqi

4,898
3
34
44

score 17 · Answer 4 · answered Mar 09 '16 at 14:58

17

Another thing to watch out for, is that this error can happen if you have a nested

<form

tag within the .Net form.

answered Mar 09 '16 at 14:58

TheAlbear

5,507
8
51
84

1

you made ma day.. 2 cents from me. – geminiousgoel Jul 27 '17 at 07:31
1

Best answer, to tell you the truth. – Daniel Almeida Aug 03 '17 at 01:56
You are right, so how to prevent it? coz sometimes we can't remove the
tag for some CSS styles
– reaz Sep 04 '17 at 15:08
1

This worked for me. Thank you. There was one in my master page, and one in a child page. – Cloud Jan 28 '20 at 03:42

score 8 · Answer 5 · answered Feb 02 '13 at 17:26

I had this same problem with a datalist I"m dynamically binding, adding EnableViewState="false" quieted the error message. I figure if I'm binding programmatically, then the control is being populated on each post back, the view state doesn't have to be maintained if it may or may not change on each call back, that's why I'm dynamically binding it, lol.

TheTechGuy · Answer 6 · 2017-09-09T08:07:50.263

7

This error can also be caused by nested <form> tag in the master page which is not allowed.

<form id="someid"></form>

This will likely be the cause if you have picked up a template and copying the code from somewhere as it.

Solution

You have to break the nesting of <form> tag. The following should become

<form method="" name="form1">
  <form method="" name="form2>
  </form>
</form>

should become

<form method="" name="form1">    
</form>

<form method="" name="form2>    
</form>

edited Sep 09 '17 at 08:07

answered Nov 03 '16 at 07:03

TheTechGuy

16,560
16
115
136

Using webforms. Took a while to realise this. – James Dec 02 '16 at 10:12
You are correct. But you also didn't mention any solutions in case the use of
tag is extremely needed.
– reaz Sep 04 '17 at 15:11
1

@reaz updated answer. The solution is obvious. The `form` tag cannot be nested. – TheTechGuy Sep 09 '17 at 08:08

score 5 · Answer 7 · edited Mar 03 '17 at 21:13

5

Add on top page

protected void Page_Load(object sender, EventArgs e)
{    
    if (!Page.IsPostBack)
    {
        //Code display data
    }
}

edited Mar 03 '17 at 21:13

Jose Rodriguez

9,753
13
36
52

answered Apr 25 '15 at 09:57

Duc Tung

59
1
1

Could you please add more details about the solution you have provided? – abarisone Apr 25 '15 at 10:26

score 4 · Answer 8 · edited Nov 17 '14 at 07:45

4

if you change UseSubmitBehavior="True" to UseSubmitBehavior="False" your problem will be solved.

<asp:Button ID="BtnDis" runat="server" CommandName="BtnDis" CommandArgument='<%#Eval("Id")%>' Text="Discription" CausesValidation="True" UseSubmitBehavior="False" />

edited Nov 17 '14 at 07:45

Baby Groot

4,637
39
52
71

answered Nov 17 '14 at 07:26

praveen

41
1
1

score 3 · Answer 9 · answered Sep 19 '11 at 20:09

Ah its unfortunate. Since you add them essentially client side asp.net blows up. It is also unfortunate you'd have to turn off EventValidation as there are some important protections that helps (for instance evil injection into drop down boxes). The other alternative is to make your own composite control, which of course here seems a bit more than the effort involved. I'd prob turn off event validation too but be very careful that you don't trust any values from the page that could be used in a bad manner by simply changing them - like hidden keys, sql injection through combo boxes, etc.

score 2 · Answer 10 · answered Dec 17 '15 at 21:01

You can also fill you data in the prerender event. This way you can keep your validation and stay secure. Here is an example using a repeater.

protected void Page_PreRender(object sender, EventArgs e)
     {
        List<Objects.User> users = Application.User.GetAllUsers();

        Repeater1.DataSource = users;
        Repeater1.DataBind();
      }

score 1 · Answer 11 · answered Jun 04 '15 at 01:43

1

My solution was to add:

ctlUpdatePanel.Update();

after binding control after postback. it was in updatepanel with UpdateMode="Conditional" attribute.

answered Jun 04 '15 at 01:43

Tone Škoda

1,463
16
20

score 1 · Answer 12 · answered Mar 23 '16 at 15:09

After having this problem on remote servers (production, test, qa, staging, etc), but not on local development workstations, I found that the Application Pool was configured with a RequestLimit other than 0.

This caused the app pool to give up and reply with the exception noted in the question.

Somewhere along the way my installshield project had its App pool definition changed to use "3" (probably just a mis-click or mis-type).

score 1 · Answer 13 · answered Aug 10 '17 at 05:09

1

You can add ViewStateMode="Disabled"

asp:UpdatePanel ID="UpdatePanel1" runat="server" ViewStateMode="Disabled"

answered Aug 10 '17 at 05:09

Jawad Siddiqui

195
1
1
15

score 0 · Answer 14 · answered Nov 06 '13 at 16:10

I had the same problem, two list boxes and two buttons.

The data in the list boxes was being loaded from a database and you could move items between boxes by clicking the buttons.

I was getting an invalid postback.

turns out that it was the data had carriage return line feeds in it which you cannot see when displayed in the list box.

worked fine in every browser except IE 10 and IE 11.

Remove the carriage return line feeds and all works fine.

score 0 · Answer 15 · edited May 23 '17 at 12:10

This is probably not the cause of your issue, but I noticed you were using optgroups in your dropdown so I figured this might help someone should they wind up here with this issue. For me, I needed to create a dropdownlist that would render with optgroups, and I ended up using the accepted answer here but while it would render the control correctly, it gave me this error. How I got past that is detailed in my answer here.

score 0 · Answer 16 · answered Jan 18 '17 at 21:04

I had a similar problem because of copy paste from another page, what I got:

<form id="form1" runat="server">
    ...
    <form id="form2" runat="server">
    ....
    </form>
</form>

I just removed form with id="form2" inside form with id="form1" and issue gone. This could be not your problem but it could be something similar.

score -3 · Answer 17 · answered Jun 29 '17 at 17:09

-3

My problem was that i had nested form tags. After removing the inner one, worked out for me.

answered Jun 29 '17 at 17:09

Blessy Khauhelo

125
1
3
11

asp.net: Invalid postback or callback argument

17 Answers17

Solution

Linked