The Customer List in the program will build up with customers either by the user adding them directly on the "Customer " Tab in the program, or by the program where it "grabs" the information for a customer as you write invoices.
If you wish to delete all the Customer information on your "Customer " Tab and start completely over, you may do so by finding and deleting specific files in the program's installation directory.
To do so, close your MyInvoices program and all other programs running on your system. Then, use your Windows "Find" or "Search" function on the START Menu to FIND and DELETE the following files:
customer.dbf
customer.dbt
customer.dbx
After you delete these files, the next time you open your program, the Customer information on the "Customer" Tab will be completely empty, (or it will contain the Customer information for the first invoice you may have just looked at).