This should get you started =)

Sub Auto_Open()
Application.OnTime Now() + TimeValue("00:30:00"), "CloseMe"
End Sub

Sub CloseMe()
ActiveWorkbook.Save
ActiveWorkbook.Close
End Sub

"Marie" wrote:

We have a worksheet that is on a shared server. On occasion someone is
distracted and fails to close the worksheet, locking it up until our PC tech
comes in. As this spreadsheet is used in the U.S., Europe, and Asia, this has
created some serious issues.
Is there a way that we can force the spreadsheet closed, if no entry has
been made to it for 30 minutes?