Удаление дубликатов и отправка письма

You can also try this

If you want to remove the duplicate rows based on one column check with this expression

(From p in DT.Select() where( From q in DT.Select() where q(“NLC”).Equals(p(“NLC”)) Select q).ToArray.Count=1 Select p).ToArray.CopyToDataTable()

If you need to get only the rows with one occurence means check with this expression

DT.AsEnumerable().GroupBy(Function(a) a.Field(Of String)(1)).Select(Function(b) b.First).CopyToDataTable()

You can also try with this

Datatable.DefaultView.Totable(true, {"list", "of", "column","names"})

Regards
Sudharsan