Forum Error

System.Web.HttpException (0x80004005): The state information is invalid for this page and might be corrupted. ---> System.Web.UI.ViewStateException: Invalid viewstate. 
	Client IP: 64.112.56.164
	Port: 40457
	Referer: 
	Path: /forum/default.aspx
	User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36
	ViewState: xYsIxPw9dKoKIxSPJ9999Gsyf2YK5y8lGxSx7LhizoTbRNbx7FbrTwAAGGhBv6yzUP5//FIP/BHHAOKfIyoyIj0TfNO6wtsHo7hkbH2SllbibVtrzJ25RQOpt91oB7DSpt8sNMak7xTtzzBA7Cd meovIbqzhNZVQCvWTMNRmkSOWWNAJAPOkYl27 xbUHreG1A0THjkCuRlfQszfq1tI9d3ykQMNW94LK/4wZFfOnqlyHwa7DZYoKanq1IziGXVrC09FlvTMgHuuKwhe/19XJAenG6nBHDZafjdwcl Oe0VPqls/DLME5h1xp Oh60 gv eKZZKeX7Ky89rHJSsw/CtzLvR0dmN4ueL0O6d8OtjI01N5KwCnvk10dZMKz/uCXd02LnFloqyzOZ/bMkPadg/0rGHer86ze4uPMaLO1rhsceZAbVrM14tDGLR30TYXnKXV5rMDRNijL U9HhT4IEHO4tICfK 0zBBL6vjv Lrv0rlSjUnzfkxIyZ43EbK8iwFrYA09VbM7y64AI4/q3T07y6DrRCK44D85bEMzAUslONKtuUduaW2yxfJCIF3xpCF8Gxv6LGcoUic0lUv/BfsSLPfiwF09u2L1r23coOmyjWx6z371TgAa9MW0MiPV9fn/8eoGMbjML0jmGQI1y24TnFJVOuDaCKKEZkq9Zui5a9VOvs8/NgjOSk5 rXaIPR9pk1/eJyWehHpN0DKaJon9d6PVKOlUOh7JRRCL gQHzSsfn9evy85BN6jaxWP4fHLjKM6NqPvy6b0c8x6d/zr  ... ---> System.FormatException: Invalid length for a Base-64 char array or string.
   at System.Convert.FromBase64_Decode(Char* startInputPtr, Int32 inputLength, Byte* startDestPtr, Int32 destLength)
   at System.Convert.FromBase64CharPtr(Char* inputPtr, Int32 inputLength)
   at System.Convert.FromBase64String(String s)
   at System.Web.UI.ObjectStateFormatter.Deserialize(String inputString, Purpose purpose)
   at System.Web.UI.Util.DeserializeWithAssert(IStateFormatter2 formatter, String serializedState, Purpose purpose)
   at System.Web.UI.HiddenFieldPageStatePersister.Load()
   --- End of inner exception stack trace ---
   at System.Web.UI.ViewStateException.ThrowError(Exception inner, String persistedState, String errorPageMessage, Boolean macValidationError)
   at System.Web.UI.HiddenFieldPageStatePersister.Load()
   at System.Web.UI.Page.LoadPageStateFromPersistenceMedium()
   at System.Web.UI.Page.LoadAllState()
   at System.Web.UI.Page.<ProcessRequestMainAsync>d__523.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Web.Util.WithinCancellableCallbackTaskAwaitable.WithinCancellableCallbackTaskAwaiter.GetResult()
   at System.Web.UI.Page.<ProcessRequestAsync>d__515.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Web.UI.Page.<ProcessRequestAsync>d__554.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Web.TaskAsyncHelper.EndTask(IAsyncResult ar)
   at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)