microsoft+access+training - Problems with numbers

It could be an issue with the field properties. Have a look at the field type, format, and decimal places settings. (make a backup of the table before modifying it, so you can go back to the original if need be.

IF you do not have any luck, you could import the DBF file to Excel, format as you require, and then reimport to Access. bear in mind that DBF is not a Microsoft product, so the integration may not be as smooth as it would be with products from the Microsoft family.