PPT Presentation Export

Getting this error when doing all slided to images, i have ms powerpoint 2016  installed and logged in and all, using windows project, :

RemoteException wrapping System.NullReferenceException: Object reference not set to an instance of an object. 

   at InternalLabs.PowerPoint.Activities.ExportPPTAsImages.ExecuteAsync(AsyncCodeActivityContext context,

CancellationToken cancellationToken)

   at UiPath.Shared.Activities.AsyncTaskCodeActivityImplementation.EndExecute(AsyncCodeActivityContext context,

IAsyncResult result)

   at UiPath.Shared.Activities.AsyncTaskCodeActivity.EndExecute(AsyncCodeActivityContext context,

IAsyncResult result)

   at UiPath.Shared.Activities.ContinuableAsyncCodeActivity.EndExecute(AsyncCodeActivityContext context,

IAsyncResult result)

   at System.Activities.AsyncCodeActivity.System.Activities.IAsyncCodeActivity.FinishExecution(AsyncCodeActivityContext context,

IAsyncResult result)

   at System.Activities.AsyncCodeActivity.CompleteAsyncCodeActivityData.CompleteAsyncCodeActivityWorkItem.Execute(ActivityExecutor executor,

BookmarkManager bookmarkManager)