it usu happens because access cant determine what data type the column is, so it guesses, and sometimes wrong.
if you have a column that has both numbers and strings, then I run a macro before import to set everything to string by putting a single quite at the front of the value.
Once your data types are set, then save the file to a generic filename, like: ImportFile.xlsx
attach the file as a table
to import just run an append query.
i sometimes run 'validation' queries to see if there is bad data before the import.
excel macro to convert data to string....
Code:
Sub Cvt2Txt()
While ActiveCell.Value <> ""
vTxt = ActiveCell.Value
If Left(vTxt, 1) <> "'" Then ActiveCell.Value = "'" & vTxt
ActiveCell.Offset(1, 0).Select 'next row
Wend
End Sub