If it is just the hardware flow control. Where should I go to access this?
It's in either the Windows Control Panel or it's in the Windows Device Manager. I don't remember which. But that's not important because the upgrade program sets all of those parameters itself before trying to connect. Setting the flow control is only important for using Hyperterminal, not for the upgrader program.
I think it is more likely to be something wrong with the cable or with the PC's serial port. For instance, bad cable, wrong kind of cable, serial port disabled in the BIOS, that sort of thing.
First, let's diagnose what's going on at the serial port level. Click
here and see if you can even see anything on the serial port at all.
Make sure to unplug the power from the player and plug it in after the software is running.
If you end up getting 2.0 final installed, afterwards make sure to check for
this problem, it's the worst of the known bugs from 2.0 Beta 11. Since you were running that version for a long time, I wouldn't be surprised if you had that problem and now needed to clean out the config file.