Option Explicit
Public Sub CreateOutlookApptz()
   Sheets("Sheet1").Select
   On Error GoTo Err_Execute
     
    Dim olApp As Outlook.Application
    Dim olAppt As Outlook.AppointmentItem
    Dim blnCreated As Boolean
    Dim olNs As Outlook.Namespace
    Dim CalFolder As Outlook.MAPIFolder
    Dim subFolder As Outlook.MAPIFolder
    Dim arrCal As String
    Dim oWS As Worksheet
    Dim i As Long
     
    On Error Resume Next
    Set olApp = Outlook.Application
     
    If olApp Is Nothing Then
        Set olApp = Outlook.Application
         blnCreated = True
        Err.Clear
    Else
        blnCreated = False
    End If
     
    On Error GoTo 0
     
    Set olNs = olApp.GetNamespace("MAPI")
    Set CalFolder = olNs.GetDefaultFolder(olFolderCalendar)
         
    i = 2
    Do Until Trim(Cells(i, 1).Value) = ""
    arrCal = Cells(i, 1).Value
    Set subFolder = CalFolder.Folders(arrCal)
     If Trim(Cells(i, 11).Value) = "" Then
    Set olAppt = subFolder.Items.Add(olAppointmentItem)
          
    'MsgBox subFolder, vbOKCancel, "Folder Name"
    Set oWS = Sheet1
    With olAppt
     
    'Define calendar item properties
        .Start = Cells(i, 4) + TimeValue("00:00:01")
        .End = Cells(i, 5) + TimeValue("23:59:59")
        .Subject = oWS.Cells(i, 2) + " " + oWS.Cells(i, 3) + " Vacation"
        .ReminderSet = True
        .Save
     
    End With
    Cells(i, 6) = "Imported"
    
    End If
    
        i = i + 1
        Loop
    Set olAppt = Nothing
    Set olApp = Nothing
     ThisWorkbook.Save
    Exit Sub
     
Err_Execute:
    MsgBox "An error occurred - Exporting items to Calendar."
     
End Sub