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. RRS feed

  • Question

  • User64294366 posted

    Hello - I a new application that I have hosted in a VMware virtual machine. When I click the submit button and the page posts back I get the Validation of viewstate MAC failed error. The application is a web forms app running under IIS 8.5 and framework 4.5.2, and the VM is running server 2012. We have no server farm.

    The vm's running under the host are in a cluster but I've been told by the server guys that VMware's definition of a cluster is not the same as Microsoft's. Each VM serves a different purpose, Dev Server, Sql Server, Production etc.

    Regardless, I clicked on Machine Key in IIS and unchecked Automatically generate at runtime. Still get the same error.  I've read many posts regarding this error and have tried many potential fixes with out results.

    Does anyone have any ideas on what could be the problem?


    Friday, May 12, 2017 2:51 PM

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