nested if statements VBA

[InWonderland]

I am trying to write a nested if statement that if column W = "Correct" and column AA is empty then the blanks will colour in. I have tried a number of different ways and I'm hoping I'm getting close with the coding below. I am doing several checks on my worksheet that's why I need this to be in vba. Can anyone help?

[COLOR=#444444][FONT=Calibri]  Dim I, j As Long

   For I = 4 To NumberOfRows[/FONT][/COLOR][COLOR=#444444][FONT=Calibri]    [/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]    For j = 1 To 52[/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]    If j = 23 Then[/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]       If Range("W4").Value = "Correct" And Range("A4").Value Then[/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]                MsgBox "No entry for " & Cells(1, 27) & " on row " & I & " ", , "MissingData"[/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]             End If[/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]          End If[/FONT][/COLOR]
[COLOR=#444444][FONT=Calibri]        [COLOR=#222222][FONT=Verdana]

[/FONT][/COLOR][/FONT][/COLOR]