Invalid Action - The Selected Action was not valid

I came across the below error when I am trying to browse my Microsoft Dynamics CRM 2011 url.

Exception message from Event Viewer:

Exception information:
    Exception type: CrmException
    Exception message: The key specified to compute a hash value is expired, only active keys are valid.  Expired Key : CrmKey(<RemovedTheKey>, ScaleGroupId:00000000-0000-0000-0000-000000000000, KeyType:CrmWRPCTokenKey, Expired:True, ValidOn:06/18/2012 03:35:21, ExpiresOn:07/21/2012 03:35:21, CreatedOn:06/18/2012 03:35:21, CreatedBy:NT AUTHORITY\NETWORK SERVICE.

I found that my CRM Asynch Service is not running. This exceptions is gone by starting the CRM Async Service.