Run Macros if Sheet Does Not Exist - vba

Question

I am trying to only run a set of macros if a sheet doesn't already exist. I have a macro that creates a sheet and combines data from two sheets into it, and another that formats the new sheet. Since it needs to run on workbook open, I can't have it recreating the sheet again and again. I have been trying the following, but it gives the error: "sub or Function not defined":
Private Sub Workbook_Open()
If SheetExist("MyNewSheet") Then
End Sub
Else
Combine
Format
End Sub

Answer 1

You aren't doing anything if the sheet exists, so change your test.
Private Sub Workbook_Open()
If Not SheetExist("MyNewSheet") Then
Combine
Format
End If
End Sub
Function SheetExist(sheetname As String) As Boolean
SheetExist = True ' replace this with code from link below
End Function
Use the answers here: Excel VBA If WorkSheet("wsName") Exists for examples of functions that determine whether the sheet exists.

Answer 2

Yea, the problem is "End Sub" should be "Exit Sub" You can also use the solution above/below.
Your fixed code would be:
Private Sub Workbook_Open()
If SheetExists("MyNewSheet") Then
Exit Sub
Else
Combine
Format
End If
End Sub
Also:
Public Function SheetExists(ByVal WorksheetName As String) As Boolean
On Error Resume Next
WorksheetExists = (Sheets(WorksheetName).Name <> "")
On Error GoTo 0
End Function