Resolve server error in MHCustomerView application when sending emails in Portrait Dialogue


The error below was reported while sending emails via the Portrait Dialogue (PD) CustomerView web application.

User-added image


This is a typical error message which is seen when the correct version of the .NET Framework is not installed.  
Similar errors will most likely be appearing when trying to access any of the PD Web Apps.


Another possibility is a "security check" problem

The RequestValidationMode property specifies which ASP.NET approach to validation will be used. This can be the algorithm that is used in versions of ASP.NET earlier than version 4, or the version that is used in .NET Framework 4. The property can be set to the following values:

  • 4.0 (the default). The HTTPRequest object internally sets a flag that indicates that request validation should be triggered whenever any HTTP request data is accessed. This guarantees that the request validation is triggered before data such as cookies and URLs are accessed during the request. The request validation settings of the pages element (if any) in the configuration file or of the @ Page directive in an individual page are ignored.

  • 2.0. Request validation is enabled only for pages, not for all HTTP requests. In addition, the request validation settings of the pages element (if any) in the configuration file or of the @ Page directive in an individual page are used to determine which page requests to validate.

The value that you assign to this property is not validated to match a specific version of ASP.NET. Any numeric value smaller than 4.0 (for example, 3.7, 2.9, or 2.0) is interpreted as 2.0. Any number larger than 4.0 is interpreted as 4.0.

To set this value in a configuration file, you can assign a value to the requestValidationMode attribute of the httpRuntime element.


UPDATED: April 24, 2017
As mentioned in the prerequisites part of the version specific Installation guide: ensure that the correct version of the ".NET Framework" has been installed on the PD server.

For example, on Windows Server 2008: For PD 6.0 ensure that the .NET Framework 4.5 has been installed on the PD server.

To get more information about the cause, we need to see the error messages that appear AFTER setting customErrors = "Off" as instructed in this error message.


A security check problem and the actual web page must be configured to bypass request validation. This can be done by adding the following section to the web.config of the Customer View application:
<!-- Pages without request validation -->
<location path="WebPages/internalemaileditor.aspx">
    <httpRuntime requestValidationMode="2.0" />