I am settign action in form tag and gettign below error:
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 have tried the following thigns:
1. Set machine config key in web.config. 2. Set EnableViewStateMac="false" in page 3. Set ViewStateEncryptionMode="Never" 4. Set  EnableEventValidation="false" but no luck. Here is markup of my page:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" EnableViewStateMac="false" ViewStateEncryptionMode="Never" EnableEventValidation="false" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http: ...

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