How to debug the 500 error on this form?

Question

I inherited a site built in VB Studio, and I am trying to get the form to work on this page: http://childplus.com/Support/ I've had a lot of 500 errors in different browsers from different users on all the forms. I just want working forms!

So far it returns a 500 error after clicking the submit button no matter the browser. However, I'm still new to using VB Studio to develop web forms. Any insight or instructions on debugging and fixing 500 errors for newbies would be greatly appreciated.

The actual form from the page:

<form id="form_support" runat="server">
<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"></asp:ToolkitScriptManager>

<!--Name-->
<div class="FormLine">
<asp:Label ID="lblName" runat="server" Text="Name:"  CssClass="Txt"></asp:Label><p class="required">(required)</p>
<asp:TextBox ID="FullName" runat="server" class="TxtBox" TabIndex="1" MaxLength="100"></asp:TextBox>
<asp:RequiredFieldValidator Display="Static" ID="RequiredFieldValFullname" runat="server" ControlToValidate="FullName"  ToolTip="Name is Required" EnableClientScript="False" SetFocusOnError="true"></asp:RequiredFieldValidator>

</div>

<!--Agency-->
<div class="FormLine">
<asp:Label ID="lblAgency" runat="server" Text="Agency:"  CssClass="Txt"></asp:Label><p class="required">(required)</p>
<asp:TextBox ID="AgencyName" runat="server" class="TxtBox" TabIndex="2" MaxLength="100"></asp:TextBox>
<asp:RequiredFieldValidator Display="Static" ID="RequiredFieldValAgencyName" runat="server" ControlToValidate="AgencyName"  ToolTip="Agency is Required" EnableClientScript="False" SetFocusOnError="true"></asp:RequiredFieldValidator><br />

</div>

<!--Email-->
<div class="FormLine">
<asp:Label ID="lblemail" runat="server" Text="Email:"  CssClass="Txt"></asp:Label><p class="required">(required)</p>
<asp:TextBox ID="email" runat="server" class="TxtBox" TabIndex="3" MaxLength="100"></asp:TextBox>
<asp:RequiredFieldValidator Display="Static" ID="RequiredFieldValEmail" runat="server" ControlToValidate="email"  ToolTip="Email is Required" EnableClientScript="False"></asp:RequiredFieldValidator>
<asp:RegularExpressionValidator  Display="Static" ID="RegularExpressionValEmail"   ErrorMessage="Email is not valid." ControlToValidate="email" runat="server" ToolTip="Email is not valid." ValidationExpression="^(['_a-z0-9-]+)(\.['_a-z0-9-]+)*@([a-z0-9-]+)(\.[a-z0-9-]+)*(\.[a-z]{2,5})$"></asp:RegularExpressionValidator>

</div>

<!--Phone-->
<div class="FormLine">
<asp:Label ID="lblPhone" runat="server" Text="Phone:"  CssClass="Txt"></asp:Label><p class="required">(required)</p>

<asp:TextBox ID="phone" runat="server" class="TxtBox" TabIndex="4" MaxLength="30"></asp:TextBox>
<asp:RequiredFieldValidator Display="Static" ID="RequiredFieldValPhone" runat="server" ControlToValidate="phone"  ToolTip="Phone is Required" EnableClientScript="False" SetFocusOnError="true"></asp:RequiredFieldValidator><br />

</div>

<!--Subject-->
<div class="FormLine">
<asp:Label ID="lblSubject" runat="server" Text="Subject:"  CssClass="Txt"></asp:Label><p class="required">(required)</p>
<asp:DropDownList ID="ddlSubject" runat="server" class="TxtBox1" TabIndex="5"></asp:DropDownList>
<asp:RequiredFieldValidator Display="Static" ID="RequiredFieldValddlSubject" runat="server" ControlToValidate="ddlSubject"  ToolTip="Subject is Required." InitialValue="" EnableClientScript="False"></asp:RequiredFieldValidator>                          

</div>

<!--Topic-->
<div class="FormLine">
<span class="Txt">Topic:</span>
<asp:DropDownList ID="ddlTopic" runat="server" class="TxtBox1" TabIndex="6"></asp:DropDownList>
<asp:CascadingDropDown ID="CascadingDropDown1" runat="server" TargetControlID="ddlSubject"  Category="subject" prompttext="Select a Subject..."  ServicePath="~/wbSubjectTopics.asmx" ServiceMethod="GetDropDownContents">
</asp:CascadingDropDown>
<asp:CascadingDropDown ID="CascadingDropDown2" runat="server" TargetControlID="ddlTopic"  Category="topic" prompttext="Select a Topic..."  LoadingText="Loading..." ParentControlID="ddlSubject" ServicePath="~/wbSubjectTopics.asmx" ServiceMethod="GetDropDownContents">
</asp:CascadingDropDown>
</div>

<!--Details-->
<div class="FormMultiLine">
<span class="Txt2">Please include as much detail as possible including:</span>
    <ul>
    <li>What steps you did.</li>
    <li>Your computer's operating system.</li>
    <li>Exact text of any error message.</li>
    </ul> 

<asp:TextBox ID="Comments" class="TxtBoxMulti" runat="server"  TextMode="MultiLine" TabIndex="7" ></asp:TextBox>                        
</div>


<!--Submit-->
<div id="SubBtnWrapper" class="SubBtnBlue">  
    <asp:LinkButton ID="SubBtn" text="" title="Submit" runat="server" TabIndex="8">
    <div class="rollover_wrapper"><div class="submit_rollover"><img src="../../Images/Forms/submit_btn_blue.png" height="78px" width="79px" /></div></div>
    </asp:LinkButton>
</div>


<script type="text/javascript" language="JavaScript"><!--    document.form_support.FullName.focus(); //--></script>
</form>

</div>

The codebehind: Imports Common

Partial Public Class Support_homepage
    Inherits System.Web.UI.Page
    Public Utils As Utils = New Utils


    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    End Sub

    Protected Sub ddlSubject_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles ddlSubject.SelectedIndexChanged
        ddlTopic.SelectedIndex = -1
    End Sub

    Private Sub SubBtn_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles SubBtn.Click
        Page.Validate()

        If (Page.IsValid) Then
            Dim EmailBody As String

            Dim strSubjectTopic As String

            If ddlTopic.SelectedValue = "" Then
                strSubjectTopic = ddlSubject.SelectedValue
            Else
                strSubjectTopic = ddlTopic.SelectedValue
            End If

            EmailBody = "<p style=" + "font-family:Verdana;" + "><strong>Technical Support Request:</strong></p><p style=" + "font-family:Verdana;" + "><strong>Name:</strong> " + FullName.Text + "</p>"
            EmailBody = EmailBody + "<p style=" + "font-family:Verdana;" + "><strong>Email:</strong> " + email.Text + "</p>"
            EmailBody = EmailBody + "<p style=" + "font-family:Verdana;" + "><strong>Phone:</strong> " + phone.Text + "</p>"
            EmailBody = EmailBody + "<p style=" + "font-family:Verdana;" + "><strong>Agency:</strong> " + AgencyName.Text + "</p>"
            EmailBody = EmailBody + "<p style=" + "font-family:Verdana;" + "><strong>Subject/Topic:</strong> " + strSubjectTopic + "</p>"
            EmailBody = EmailBody + "<p style=" + "font-family:Verdana;" + "><strong>Comments:</strong> " + Comments.Text + "</p>"

            Utils.SendAppNotificationEmails("support@childplus.com", "support@childplus.com", "Website: Technical Support Request", EmailBody)
            Response.Redirect("/")
        Else
            If RequiredFieldValFullname.IsValid Then
                lblName.CssClass = "Txt"
            Else
                lblName.CssClass = "ErrorTxt"
            End If

            If RequiredFieldValAgencyName.IsValid Then
                lblAgency.CssClass = "Txt"
            Else
                lblAgency.CssClass = "ErrorTxt"
            End If

            If RequiredFieldValPhone.IsValid Then
                lblPhone.CssClass = "Txt"
            Else
                lblPhone.CssClass = "ErrorTxt"
            End If

            If RequiredFieldValEmail.IsValid Then
                lblemail.CssClass = "Txt"
            Else
                lblemail.CssClass = "ErrorTxt"
            End If


            If RequiredFieldValddlSubject.IsValid Then
                lblSubject.CssClass = "Txt"
            Else
                lblSubject.CssClass = "ErrorTxt"
            End If
        End If
    End Sub


End Class

Here's the stack trace:

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) +8644665
   System.Web.UI.Control.ValidateEvent(String uniqueID, String eventArgument) +69
   System.Web.UI.WebControls.DropDownList.LoadPostData(String postDataKey, NameValueCollection postCollection) +53
   System.Web.UI.WebControls.DropDownList.System.Web.UI.IPostBackDataHandler.LoadPostData(String postDataKey, NameValueCollection postCollection) +13
   System.Web.UI.Page.ProcessPostData(NameValueCollection postData, Boolean fBeforeLoad) +343
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1743

Try to post some code which is actually causing you the 500 errors. — Tariqulazam, Oct 15 '12 at 20:40
could you please post the error details preferably with the stack trace? — Tariqulazam, Oct 15 '12 at 23:49
The general 500 error is not giving a clue about your problem. See this answer http://stackoverflow.com/questions/5385714/deploying-website-500-internal-server-error/5385884#5385884 — Aristos, Oct 16 '12 at 05:57
@Aristos, thank you for that link. It helped me turn off the custom error pages. — Tamara, Oct 16 '12 at 15:48
@Tariqulazam, I just added the actual error information for the page in question. — Tamara, Oct 16 '12 at 15:55
@Tamara - How the databinding to the dropdownlist works? I am pretty sure the problem is there. — Tariqulazam, Oct 16 '12 at 20:22

score 0 · Answer 1 · answered Oct 16 '12 at 20:27

0

Try the solution described in this article http://johanleino.wordpress.com/2011/04/09/revisedcascadingdropdown-casues-invalid-postback-or-callback-argument-error/

answered Oct 16 '12 at 20:27

Tariqulazam

4,425
1
35
40

How to debug the 500 error on this form?

1 Answers1