VBA to throw a prompt when clicked on protected cell - vba

Question

I have Workbook with both Sheet/workbook is protected.
I have a code to lock/disable certain range of cells when the drop-down value "no" And unlock/enable when value of drop down is "yes"
Whereas, drop-down value and cells I would like to disable are on different sheets.
Dropdown on "Main Sheet"
Range of cells on "Sub Sheet"
I also need to throw a prompt to user when he clicks on protected range and when the value is set to "No".
I am using following code on "Main Sheet"
Private Sub Worksheet_Change(ByVal Target As Range)
Dim worksh As Integer
Dim worksheetexists As Boolean
Dim str1 As String
If UCase$(Range("E30").Value) = "YES" Then
Sheets("SubSheet").Select
Sheets("SubSheet").Range("E20:I3019").Locked = False
Sheets("SubSheet").Range("E20:I3019").Activate
Else
Sheets("SubSheet").Range("E20:I3019").Locked = True
End If
End Sub
Following code on Sub Sheet
Private Sub WorkBook_SheetChange(ByVal sh as Object, ByVal Target as Range)
If Intersect (Target, sh.Range("$E$19:$I$3000")) Is Nothing Then Exit Sub
MsgBox "Please select the appropriate dropdown on MAIN Sheet " & Target.Address
With Application
.EnableEvents = False
.UnDo
.EnableEvents = True
End With
End Sub
Not sure, where am I going wrong as Its not throwing prompt when user clicks on protected cells.

Answer 1

First. You should remove the Sheets("SubSheet").Select. If you running your code and your are not inside the sheet, it could occur an error. try to do:
with ThisWorkbook.Sheets("SubSheet")
If UCase$(Range("E30").Value) = "YES" Then
.Range("E20:I3019").Locked = False
.Range("E20:I3019").Activate
Else
.Range("E20:I3019").Locked = True
End If
end with
Second. You don't return the target range. I mean your Private Sub WorkBook_SheetChange waits for a ByVal Target as a parameter and your Private Sub Worksheet_Change returns any value.It should be a function returning the range or the cell you have selected for me.
EDIT:
with ThisWorkbook.Sheets("SubSheet")
If UCase$(Range("E30").Value) = "YES" Then
.Range("E20:I3019").Locked = False
Else
.Range("E20:I3019").Locked = True
WorkBook_SheetChange Range("E20:I3019")
End If
end with
And
Private Sub WorkBook_SheetChange(ByVal Target as Range)
If Intersect (Target, Range("$E$19:$I$3000")) Is Nothing Then Exit Sub
MsgBox "Please select the appropriate dropdown on MAIN Sheet " & Target.Address
With Application
.EnableEvents = False
.UnDo
.EnableEvents = True
End With
End Sub