Runtime error '1004': application or object defined error - excel

Question

Runtime error '1004': application or object defined error
Hey I cant find out why my code isn't working. I know it's somewhere in the right hand side of the formula. I've highlighted the error for you.
Private Sub CommandButton1_Click() 'accept button
Blank:
machine = TextBox1.Value
rates = TextBox2.Value
If machine = "" Then 'if blank
MsgBox ("Please type in a machine name.")
GoTo DONE
ElseIf rates = "" Then 'if rates is blank
MsgBox ("Please type in a rate for machine.")
GoTo DONE
End If
For i = 1 To 50 'search database
If LCase(Worksheets("database").Cells.Range("B2").Offset(0, i)) = LCase(machine) Then 'if name is in database
MsgBox (machine & " is already in database. Choose another name.")
GoTo DONE
ElseIf IsEmpty(Worksheets("database").Cells.Range("B2").Offset(0, i)) Then 'if it's not
Range("B:B").Offset(0, i).Select
Selection.Insert Shift:=xlToRight, CopyOrigin:=xlFormatFromLeftOrAbove
Worksheets("database").Cells.Range("B2").Offset(0, i) = machine
Worksheets("database").Cells.Range("B2").Offset(0, i).HorizontalAlignment = xlLeft
Worksheets("database").Cells.Range("B2").Offset(-1, i) = rates
For j = 1 To 50
If LCase(Range("A1").Offset(j, 0)) = "total hours" Then
ActiveSheet.Range("B1").Offset(j, i).Formula = "=sum(" & Range(Cells(3, i + 2), Cells(j, i + 2)).Address(False, False) & ")"
ActiveSheet.Range("B1").Offset(1 + j, i).Formula = "=product(sum(" & ActiveSheet.Range(Cells(3, i + 2), Cells(j, i + 2)).Address(False, False) & "," & ActiveSheet.Range(Cells(1, 2 + i)) & ")"
GoTo Cancel
End If
Next j
GoTo Cancel
End If
Next i
Cancel:
DONE:
End Sub
the line that i separate from the others is the one in question.
Thanks!

Answer 1

Hard to know without a description of what you are trying to do. But perhaps:
"=product(sum(" & ActiveSheet.Range(Cells(3, I + 2), Cells(J, I + 2)).Address(False, False) & "," & ActiveSheet.Cells(1, 2 + I).Address & "))"

Answer 2

You need to analyze each part of the line by itself to see what is causing the error. Then put them together after verifying the parts.
Dim HoursRangeAddress As String
Dim RateRangeAddress As String
HoursRangeAddress = ActiveSheet.Range(Cells(3, i + 2), Cells(j, i + 2)).Address(False, False)
RateRangeAddress = ActiveSheet.Cells(1, i + 2).Address
Debug.Print HoursRangeAddress
Debug.Print RateRangeAddress
ActiveSheet.Range("B1").Offset(1 + j, i).Formula = _
"=product(sum(" & HoursRangeAddress & ")," & RateRangeAddress & ")"
You were missing a parenthesis ) after your sum. But also this caused an error: ActiveSheet.Range(Cells(1, 2 + i)) Try this instead: ActiveSheet.Cells(1, 2 + i).Address
Using R1C1 Notation: You should really learn R1C1 notation. Once you are familiar with it, your code is much easier to write and read. You can replace all of the lines of code above with this one line:
ActiveSheet.Range("B1").Offset(1 + j, i).FormulaR1C1 = "=R1C*R[-1]C"
I understand now that you are trying to multiply the rate in row one by the total hours one row above this formula.
It's so much better to use R1C1 notation in a situation like this. You can avoid entirely the need to create string addresses for the formulas. Your formula becomes very simple and easy to read.