So I'm a little new with excel, but programming in VBA is fun so I took on a little project involved consuming data from a webservice. The workflow went like this:

1. Poll web service
2. Drop new records in designated named range
3. Run again in 30 seconds

I scheduled a subroutine to perform this using Application.Ontime. The problem was, when i closed the workbook, it kept on opening the workbook back up. So I had to figure out a way to cancel the scheduled subroutine. You do this by setting schdeule=false, but you have to pass in the same time that it was schedule for in the earliest time param. Here's how you do it:

Public RunWhen As Double - I put this in a module called mPublic 

Private Sub Workbook_Open()
    Time_set
End Sub

Private Sub Workbook_BeforeClose(Cancel As Boolean)
    Bye_Bye
End Sub

Sub Time_set()
    RunWhen = Now + TimeValue("00:00:30")
    Application.OnTime RunWhen, "time_set"   
    DoWork

End Sub 

Sub Bye_Bye()
     Application.OnTime EarliestTime:=RunWhen, Procedure:="time_set", Schedule:=False

End Sub

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