i have a trouble in importing data to sql server database from access database

When i import data from a access database to a sql server database, only the tabe structures are imported, no data is imported, the process showed a message notes the datetime data error. I used the sql server enterprise to do this job. I don't know exectly why it has error while it has no error if i use upsizing wizard in Access xp. Somebody help me.

thank you all

Is the date field a datetime or a smalldatetime? There are sometime problems if the dates are outside the "normal" range and smalldatetime is selected