What you could do is name the macro "AutoExec". This will have it run when the database opens. Then you can open up the database at a certain time using Windows Task Scheduler. The syntax to open up the DB is C:\AccessPath\msaccess.exe c:\DBPath\DbName.mdb. At the end of the macro, add the Quit action, so Access will close automatically after the macro is completed. If you want to open the database in the future without running the AutoExec macro, you'll have to hold down the shift button while you open up access. Hope that helps.
Doug