Forms authentication failed for the request. Reason: The ticket supplied was invalid.
Monday, 22 December 2008

If you get the error

Forms authentication failed for the request. Reason: The ticket supplied was invalid

You need sure that the <machinekey> is the same for all of the machines in the cluster

There is more information about this problem in the following article http://msmvps.com/blogs/omar/archive/2006/08/20/108307.aspx

Thanks to Omar AL Zabir for this info
Last Updated ( Tuesday, 24 November 2009 )