files don't correlate correctly with the data (sdt) or hdr (shd) files.
Report errors if either the data or hdr file are not a logical length
(e.g. not evenly divisble by the block length).
Report the oldest message (in days) in the msgbase, from import date/time.

ToDo: report messages posted/imported (or written) in the future
ToDo: keep the stats in an array for sensible clearing and reporting