Store.IsDataFileStore Property (Outlook)
Returns a Boolean that indicates if the Store is a store for an Outlook data file, which is either a Personal Folders File (.pst) or an Offline Folder File (.ost). Read-only.
IsDataFileStore supports only Exchange stores, and will return False for HTTP-type stores such as Hotmail and MSN, and for IMAP stores.
For Exchange stores, IsDataFileStore will return False if the user profile is not using Cached Exchange mode. IsDataFileStore will also return False when the store is an Exchange Public Folder (that is, Store.ExchangeStoreType is olExchangePublicFolder).
IsDataFileStore does not indicate whether the store is located on a local hard drive. For example, a .pst file could be located on a mapped network drive and IsDataFileStore would still return True.
The return value of IsDataFileStore can change if the user is configured for classic Exchange offline mode. When the user is offline and using classic Exchange offline mode, IsDataFileStore will return True. When the user is online and using classic Exchange online mode, IsDataFileStore will return False.