Server Error in '/' Application. 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. See http://go. microsoft.com/fwlink/?LinkID=314055 for more information. An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. System. Web. HttpException: 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. See http://go. microsoft.com/fwlink/?LinkID=314055 for more information. c:\\Windows\\Microsoft. NET\\Framework64\\v4.0.30319\\Temporary ASP. NET Files\\root\\4e4abb37\\3819fa3d\\App_Web_default.aspx. cdcab7d2. adqasonq.0. cs 0 System. Web. UI. ViewStateException. ThrowMacValidationError +12531356 System. Web. UI. ObjectStateFormatter. Deserialize +12424295 System. Web. UI. Util. DeserializeWithAssert(IStateFormatter2 formatter, String serializedState, Purpose purpose) +67 System. Web. UI. HiddenFieldPageStatePersister. Load +12424507 System. Web. UI. Page. LoadPageStateFromPersistenceMedium +12678373 System. Web. UI. Page. LoadAllState +51 System. Web. UI. Page. ProcessRequestMain +12671271 System. Web. UI. Page. ProcessRequest +12670781 System. Web. UI. Page. ProcessRequest +119 System. Web. UI. Page. ProcessRequest +99 ASP. default_aspx. ProcessRequest in c:\\Windows\\Microsoft. NET\\Framework64\\v4.0.30319\\Temporary ASP. NET Files\\root\\4e4abb37\\3819fa3d\\App_Web_default.aspx. cdcab7d2. adqasonq.0. cs:0 System. Web. CallHandlerExecutionStep. System. Web. HttpApplication. IExecutionStep. Execute +913 System. Web. HttpApplication. ExecuteStep +165 Microsoft. NET Framework Version:4.0.30319; ASP. NET Version:4.0.30319.34237 SENEDIR FORUMLARINIZDAYIM BI COZEMEDINIZ