Can anyone tell me why I get the following error when running the code
below?

Method 'OnTime' of object'_Application failed

I have the following items in a public module

Public Const cRunIntervalSeconds = 30 'Time interval for pulling updated
data from Calendar (in seconds)
Public Const cRunWhat = "TheSub" ' the name of the procedure to run
Public Const SPLASH_MINUTES = 1 'Time interval for the Close Splash screen
(in minutes)
Public Const NUM_MINUTES = 100 'Time interval for closing the workbook(in
minutes)
Public bSELCTIONCHANGE As Boolean
Public Cancel As Boolean
Public RunWhen As Double
Public RunWhenSplash As Boolean



Private Sub Workbook_BeforeClose(Cancel As Boolean)
RunWhenSplash = Now + TimeSerial(0, SPLASH_MINUTES, 0)
Application.OnTime RunWhenSplash, "ShowMySplash", , False
End Sub