Validation of viewstate MAC failed

Hello Friends
i was getting the error in my asp.net application like this

Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.
i googled it and got 791 results.
i tried every possible solutions but could not solve my problem
then finally i got one solution, tried that and bingo it worked

here is the solution:
http://www.orcsweb.com/articles/aspnetmachinekey.aspx
this link generates machine key automatically
and also generates codes for web.config file
just copy paste that code in web.config file
and run ur application again.
contact me if u cant solve it
info@amitech.co
www.amitech.co