One thing I have often done is to either place/or call my code to run in the "Workbook_Open" event procedure in VBA. This will cause the macro to run automatically upon opening the file.
Then, I will use something like Windows Scheduler to automatically open the file at my desired time and day, which will open the file, and then the Workbook_Open event will cause my code to run.
If you use this method, just be sure to add a line of code at the bottom of the "Workbook_Open" event to automatically close the workbook too.
There are other similar methods you can find with a simple Google search, like this one:
Learn how to utilize a few programs you already have to create automation rules that will automatically open up your Excel files, run VBA code, save the changes, and then close the file. These automations can even be setup to run while you sleep!
www.thespreadsheetguru.com