A while back we were having the occasional issue on the web farm with the view state validation failing- this was due to the machine key differing on the two machines on the farm so the view state was being encrypted on one machine then posted back and the other machine was picking up the request and trying to decrypt with it’s own key.
We resolved this by updating the machine.config file on both machines and generating a fixed machine key which we got from the EggHeadCafe.com site – being in the machine config means this will apply for any website hosted on that server.
Incidentally, the machine.config file is located a;
%windir%\Microsoft.NET\Framework\<version>\config\machine.config
Related posts:
