I should have qualified the 'occurrences without determinations' with say, ' already in the database you are importing the data into'. If Recorder 6 crashes when doing data entry using one of the options on the Data Entry menu I have seen it create the survey event, sample and taxon occurrence but not the determination - see http://forums.nbn.org.uk/viewtopic.php?pid=4539#p4539 . If this has happened several times, your database may contain several taxon occurrences without determinations. If you then import a file containing a small number of observations, i.e. fewer than the number of taxon occurrences without determinations, the import will delete the occurrences without determinations and import the observations in the import file and report that it has imported a negative number of observations.
Taxon occurrences without determinations are a minor form of corruption which users should tidy up. Hence my comments that ‘Taxon name missing or not in dictionary’ should be displayed when appropriate and that we could really do with a suite of XML reports that look for problems like these to give users an opportunity to correct them. I have also seen occurrences with more than one preferred determination and occurrences with determinations but without a preferred one, neither of which are valid. Samples without occurrences may be something that should be tidied up as well although probably not survey events without samples. In Recorder 3 to Recorder 6 data transfers, R3 events are transferred as survey events with nothing in them.
Without doing the tests on your database myself, I can't explain your point that 'it would not occur when I tried the import the second time, or the third and it did' as I don't know exactly when it does the deletion.
Sally Rankin, JNCC Recorder Approved Expert
E-mail: s.rankin@btinternet.com
Telephone: 01491 578633
Mobile: 07941 207687