i made a mistake when i add ajax toolkit 4.0 to visual studio 2008.
Since then i do get Run time error which is 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.
And after i realize that it was ajax 4.0 i deleted it but it was still giving the same error.
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