Issue: Webconsole.log has ValidateHeaderAntiForgeryTokenAttributeError

The Issue:

You have an error that matches the below screenshot in your webconsole.log:

The Fix: Generating the machine key

The reason you are seeing these errors is either because the machine key on the server is changing when the application restarts, or because you have multiple portal servers behind a load balancer. Setting the same machineKey across all of the servers should ensure that incoming requests are successfully handled by any of the servers.

The first step is to ensure all web servers in a web farm are using the same machine key. This key can be generated and copied in IIS:

Open IIS Manager, select the CiresonPortal web site, and double click Machine Key in the ASP.NET section.

Untick the options to automatically generate the key at runtime, and then click Generate Keys and then Apply.

Open the web.config file in the folder C:\inetpub\CiresonPortal, and you should find a machineKey entry has been added to the system.web section.

If you have more than one portal server, you must copy this machineKey from the web.config file on this server to the machine.config files on the other servers. They should all be using the same keys so that an authentication cookie generated by one server can be authenticated by another.

To ensure the machine key settings persists across portal updates, the machine key tag can be entered into the machine.config file in the .Net config folder. This is typically C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config.
The tag is entered under system.web section:

Save the web.config file.

Save the machine.config file.

End of document.