Runtime error in VBA Excel - vba

Question

I am comparing two column D and E in my sheet which are containing Dates.
The column E has date and sometime there are no Dates and sometime it has X, in the row. I get an runtime error
type mismatch
Could anyone suggest what is wrong with my code. ?
Sub datecompare()
Dim ws As Worksheet
Dim lRow As Long, i As Long
Dim zWeeks As Double, zcolour As Long
Dim Ztext As String
Set ws = Sheets("Preparation Sheet")
With ws
lRow = .range("D" & .Rows.Count).End(xlUp).Row
For i = 2 To lRow
zWeeks = DateDiff("ww", .range("E" & i).Value, .range("D" & i).Value)
If .range("A" & i).Value <> "" And .range("B" & i).Value <> "" And .range("E" & i).Value = "" Then
Ztext = "remaining"
zcolour = vbYellow
Cells(i, 7) = "Yellow"
ElseIf .range("B" & i).Value = "" And .range("E" & i).Value = "" Then
GoTo nextrow
ElseIf zWeeks < 4 Then
Ztext = " on time"
zcolour = vbGreen
Cells(i, 7) = "Green"
ElseIf zWeeks > 8 Then
Ztext = " delayed"
zcolour = vbRed
Cells(i, 7) = "Red"
ElseIf zWeeks > 4 < 8 Then
Ztext = "remaining"
zcolour = vbYellow
Cells(i, 7) = "Yellow"
End If
With .range("F" & i)
.Value = Ztext
.Interior.Color = zcolour
End With
nextrow:
Next i
End With
End Sub
The error occurs at
GoTo nextrow
and it jumps to next, without running through the in between code.

Answer 1

I think, the code woult to be like this.
Sub datecompare()
Dim ws As Worksheet
Dim lRow As Long, i As Long
Dim zWeeks As Double, zcolour As Long
Dim Ztext As String
Set ws = Sheets("Preparation Sheet")
'Cells.Interior.Color = xlNone
With ws
lRow = .Range("D" & .Rows.Count).End(xlUp).Row
For i = 2 To lRow
If IsDate(.Range("E" & i).Value) And IsDate(.Range("D" & i).Value) Then
Else
GoTo nextrow
End If
zWeeks = DateDiff("ww", .Range("E" & i).Value, .Range("D" & i).Value)
If .Range("A" & i).Value <> "" And .Range("B" & i).Value <> "" And .Range("E" & i).Value = "" Then
Ztext = "remaining"
zcolour = vbYellow
Cells(i, 7) = "Yellow"
Else '<~~ .Range("A" & i).Value <> "" And .Range("B" & i).Value <> "" And .Range("E" & i).Value = "" true or false , this is false
If .Range("B" & i).Value = "" And .Range("E" & i).Value = "" Then
GoTo nextrow
Else '<~~ .Range("B" & i).Value = "" And .Range("E" & i).Value = "" Then true or false, this is false
'<~~ When the result is false, after code applied
If zWeeks < 4 Then
Ztext = " on time"
zcolour = vbGreen
Cells(i, 7) = "Green"
ElseIf zWeeks > 8 Then
Ztext = " delayed"
zcolour = vbRed
Cells(i, 7) = "Red"
ElseIf zWeeks >= 4 And zWeeks <= 8 Then
Ztext = "remaining"
zcolour = vbYellow
Cells(i, 7) = "Yellow"
End If
End If
End If
With .Range("F" & i)
.Value = Ztext
.Interior.Color = zcolour
End With
nextrow:
Next i
End With
End Sub