You need to escape your backslahes, if you’re doing this from vision (including the console): C:\\Program Files\\Inductive Automation\\Ignition\\webserver\\webapps\\main\\ProductionReport.xls
The pythonic way would be to use forward slashes. C:/Program Files/Inductive Automation/Ignition/webserver/webapps/main/ProductionReport.xls
That said, this only works if you’re doing this on the same machine the gateway is running on.
If you’re already putting the file into /webserver/webapps/main, then you can just direct the user to ${gatewayAddress}/fileName.xls and the browser should automatically download the file.