If your Sales Invoice PDF is saving as 'XXX', please do the following:
Click Options.
Click System Maintenance.
Click Document Layouts.
Click Document Layouts.
Against the 'Sales Invoice' row, click the '>' under the 'Output Defaults' column and press F5.
Select 'Invoice' and click OK.
Re-type the 'XXX' in 'Invoice_XXX' under the 'Filename' and click OK.
