umbraco v4.0.3 (Assembly version: 1.0.3625.27276)
asp.net 2.0 integrated pipeline
Windows 2008 server and IIS 7

Setting a "publish at" or "remove at" date on a page does not work every time. I have tried setting date/times 10, 20, 30, etc. minutes ahead of the current date/time and sometimes it works and sometimes it does not work. Also, when setting a date/time for early in the AM I receive the following error below (stack trace) when clicking on any page in the Content section after the date and time has passed.

Are there specific requirements my server needs to have in order for this to work? My clients need this functionality and I am hoping this can be resolved quickly.

Stack Trace:

Error publishing node: System.TypeInitializationException: The type initializer for 'umbraco.cms.businesslogic.datatype.controls.Factory' threw an exception. ---> System.NullReferenceException: Object reference not set to an instance of an object. at umbraco.BusinessLogic.Utils.TypeFinder.FindClassesOfType[T](Boolean useSeperateAppDomain) at umbraco.cms.businesslogic.datatype.controls.Factory.Initialize() at umbraco.cms.businesslogic.datatype.controls.Factory..cctor() --- End of inner exception stack trace --- at umbraco.cms.businesslogic.datatype.DataTypeDefinition.get_DataType() at umbraco.cms.businesslogic.property.Property.MakeNew(PropertyType pt, Content c, Guid versionId) at umbraco.cms.businesslogic.Content.createNewVersion() at umbraco.cms.businesslogic.web.Document.PublishWithResult(User u) at umbraco.cms.businesslogic.web.Document.Publish(User u) at umbraco.presentation.publishingService.CheckPublishing(Object sender)

Thanks, any help would be appreciated.