I am new to JMeter, I recorded a script and executed and found following error.

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.

The source code that generated this unhandled exception can only be shown when compiled in debug mode. To enable this, please follow one of the below steps, then request the URL:
1. Add a "Debug=true" directive at the top of the file that generated the error.
Example: **<%@ Page Language="C#" Debug="true" %> or:
2) Add the following section to the configuration file of your application:

<configuration> ***
<system.web> *******
<compilation debug="true"/> ***

I opened my web.config file and found compilation tag, i changed debug=true (earlier was false) then rerun JMeter recorded script but still same error,no any other information given.

Do you have any R&D how to fix this issue?