Hundreds of Windows event log error messages Retrieving the COM class factory...

Hi all,

Our NAV2009 service tier server is reporting hundreds of error messages, all the same:

Type: System.Runtime.InteropServices.COMException
ErrorCode: -2147221164
Message: Retrieving the COM class factory for component with CLSID {CD4D86E3-C704-4D20-AB91-D2BACDF6964B} failed due to the following error: 80040154.
StackTrace:
at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandle& ctor, Boolean& bNeedSecurityCheck)
at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean fillCache)
at System.RuntimeType.CreateInstanceImpl(Boolean publicOnly, Boolean skipVisibilityChecks, Boolean fillCache)
at System.Activator.CreateInstance(Type type, Boolean nonPublic)
at Microsoft.Dynamics.Nav.Types.NavAutomationHelper.CreateAutomationObject(Guid classId, String licenseKey, Boolean newServer)
at Microsoft.Dynamics.Nav.Runtime.NavAutomation.Create(DataError errorLevel, Boolean newServer, Boolean clientSide)
Source: mscorlib

No users are reporting any specific problems with NAV2009, so I'm trying to figure out what is going on.

Any ideas on how to isolate what is causing this?

Thx

Ron