How to configure machineKey

Hi,

I'm getting the following error from pages that uses AntiForgeryToken:

"Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster."

I guess that I need to configure machineKey in web.config, but with which values, what are the setting of validationKey on your end?

 

That is the one I use, it does a great job ---> http://aspnetresources.com/tools/keycreator.aspx