Problem Filter Data Table not working

@NHoe

sounds like grouping data

(From d in YourDataTable.AsEnumerable
Group d by k=d(“Auftragsnummer”).toString.Trim into grp=Group
Where grp.Count > 1
Select g=grp.CopyToDataTable).toList

it will group all rows with same ANummern when group count > 1 into a seperate datatable.
The return is alist of datatable, each datatable will contain the rows from one group