Fill a combobox from another sheet

Hi to all
I want to fill a combobox from another sheet
When i use this code

With Me.ComboBox_1
    .Clear
    .List = Worksheets("Kkin").Range(Cells(2, 1), Cells(LRCombobox_1, LCCombobox_1)).Value
    '.List = Worksheets("Kkin").Range("A2", "D4").Value

End With

I get run-time error 1004.
Why???
If i use the rem line work without issues....

You need to qualify all range/cells references with sheet name.

with Worksheets("Kkin")
 .List = .Range(.Cells(2, 1), .Cells(LRCombobox_1, LCCombobox_1)).Value
end with

Thanks StephenR.

It work like a charm