C# 8000401a 服务器进程无法启动，因为配置的身份不正确

如何解决C# 8000401a 服务器进程无法启动，因为配置的身份不正确

我正在尝试使用 office 组件将 excel 文件转换为 pdf 文件，但出现异常

<exception><![CDATA[System.Runtime.InteropServices.COMException (0x8000401A): Retrieving the COM class factory for component with CLSID {00024500-0000-0000-C000-000000000046} Failed due to the following error: 8000401a The server process Could not be started because the configured identity is incorrect. Check the username and password. (Exception from HRESULT: 0x8000401A).
   at System.Runtime.Remoting.RemotingServices.AllocateUninitializedobject(RuntimeType objectType)
   at System.Runtime.Remoting.Activation.ActivationServices.CreateInstance(RuntimeType serverType)
   at System.Runtime.Remoting.Activation.ActivationServices.IsCurrentContextOK(RuntimeType serverType,Object[] props,Boolean bNewObj)
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type,Boolean publicOnly,Boolean noCheck,Boolean& canBeCached,RuntimeMethodHandleInternal& ctor,Boolean& bNeedSecurityCheck)
   at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly,Boolean skipCheckThis,Boolean fillCache,StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(Type type,Boolean nonPublic)
   at System.Activator.CreateInstance(Type type)
]]></exception>   

但是，当我重新启动 IIS 时，一切正常。差不多两天后，异常再次出现。