Fn key not working in Acer Aspire 4315 Notebook

the link does not work Some of the Fn/F combination hot keys - including Fn/F5 apparently - don't work unless Acer Launch Manager is running. Start, Run, type MSCONFIG, OK, Startup Tab, check QtZgAcer if it's unchecked, OK, Restart PS - You must continue to hold down the Fn key after clicking and lettting go of the F5 key - a little screen will open after a few seconds and you can move across the choices by clicking F5 1, 2 or 3 more times (while continuing to hold down Fn). I.e., it's not like Cntl, Alt, Delete, where you can let go of each key after clicking it. the link does not work Some of the Fn/F combination hot keys - including Fn/F5 apparently - don't work unless Acer Launch Manager is running. Start, Run, type MSCONFIG, OK, Startup Tab, check QtZgAcer if it's unchecked, OK, Restart PS - You must continue to hold down the Fn key after clicking and lettting go of the F5 key - a little screen will open after a few seconds and you can move across the choices by clicking F5 1, 2 or 3 more times (while continuing to hold down Fn). I.e., it's not like Cntl, Alt, Delete, where you can let go of each key after clicking it.