Hi, this is just for information.
In the past I've had a problem updating my 1640 to a newer firmware.
All the programs work well with the writer only the firmware-update-program can't see the writer (the 1640 didn't appear in the listbox).
After making a fresh WinXP installation the writer is selectable in the firmware-program.
Then I installed the drivers step by step and tested the firmware-program.
After installing the VIA IDE Accelerator the writer is gone in the firmware-program. Going back to the MS IDE drivers solved that issue.
I've tried the same on my old XP installation and the MS drivers are shown in the device-manager too but the firmware-program can not see the 1640.
I seems that the VIA driver are very obstinate.
Only a fresh WinXP solved the problem.