I am getting the owner of one domain complaining that a large number of what he calls spam are getting through the filter (SFI v 3.1.3.605).

The last time I saw this happen I had to delete the contents or the corpus folder (the database) as it was suspected corrupt.

The logs are showing quite a few entries similar to this:

04/16/07 17:11:53:750 -- (2568) TSpamFilterForm - Begin LoadFromFile for corpus.db (db.dat)
04/16/07 17:11:53:812 -- (2568) TSpamFilterForm - LoadFromFile for Corpus.db - copied db.dat -> IndD1A8.tmp
04/16/07 17:11:53:812 -- (2568) TSpamFilterForm - LoadFromFile for Corpus.db - copied db.dat.prb -> IndD1A9.tmp
04/16/07 17:11:53:812 -- (2568) TSpamFilterForm - corpus.db copy of files not exist - exiting
04/16/07 17:11:53:812 -- (2568) TSpamFilterForm - End LoadFromFile for corpus.db (db.dat) (0)
04/16/07 17:11:53:812 -- (2568) SpamFilterForm - corpus.db cannot be loaded, waiting 60 seconds
04/16/07 17:11:53:953 -- (79024) SFDB - Added 82.201.227.41 - Response: Error=0
04/16/07 17:11:53:953 -- (79024) Disconnect
04/16/07 17:11:54:078 -- (2564) TBayesianThread - Begin LoadFromFile for corpus.db (db.dat)
04/16/07 17:11:54:078 -- (2564) TBayesianThread - LoadFromFile for Corpus.db - copied db.dat -> IndD1AA.tmp
04/16/07 17:11:54:078 -- (2564) TBayesianThread - LoadFromFile for Corpus.db - copied db.dat.prb -> IndD1AB.tmp
04/16/07 17:11:54:078 -- (2564) TBayesianThread - corpus.db copy of files not exist - exiting
04/16/07 17:11:54:078 -- (2564) TBayesianThread - End LoadFromFile for corpus.db (db.dat) (0)
04/16/07 17:11:54:078 -- (2564) SpamFilterForm - corpus.db cannot be loaded, waiting 60 seconds

I have just discovered that the server went down unexpectedly on 3rd April.  Could this be the problem and what can I do (apart from the obvious of UPS protection - if it was in fact a power glitch) to prevent it happening in the future.

Thanks for your help