Add-ins tab not showing - have tried everything!

CA18UK Just so we know whether there isn't something amiss, try this:

- Paste below code into a new module and run the sub called CreateMenu

- Go to Excel and see if the add-ins tab appears

- Run the routine RemoveMenu to remove it again

Sub CreateMenu()
    Dim oMainCtl As Object
    Dim oCTl As Office.CommandBarControl
    Set oMainCtl = Application.CommandBars("Worksheet Menu Bar").FindControl(ID:=30007, recursive:=True)
    On Error Resume Next
    oMainCtl.Protection = msoBarNoProtection
    Set oMainCtl = oMainCtl.Controls.Add(Type:=msoControlPopup, temporary:=True)
    With oMainCtl
        .Caption = "&Testing Main Menu"
        .Tag = "FOOBAR"
    End With

    Set oCTl = oMainCtl.Controls.Add(Type:=msoControlButton, temporary:=True)
    With oCTl
        .Caption = "Testing"
        .Style = msoButtonIconAndCaption
        .FaceId = 486
        .Tag = "FOOBAR"
        .OnAction = "'" & ThisWorkbook.Name & "'!Foobar"
    End With
End Sub

Sub foobar()
    MsgBox "it works"
End Sub

Sub RemoveMenu()
    Dim oCTl As CommandBarControl
    For Each oCTl In Application.CommandBars("Worksheet Menu Bar").FindControl(ID:=30007, recursive:=True).Controls
        If oCTl.Tag = "FOOBAR" Then
            oCTl.Delete
        End If
    Next
    Set oCTl = Nothing
End Sub