C759 won't accept firmware

[mascan42]

I have a problem at an account where I'm trying to update the firmware on all of their machines. They have 4 C759s - two of which won't boot up into the USB firmware. The black dot in the corner of the screen doesn't even show up when I boot up holding the stop button. The other two machines updated with no problem using the same USB drive.

The two machines that fail seem to boot up very quickly, as though they're skipping some of the steps - they come up to the three pillars screen in just a few seconds. Any idea what could be causing this?

[tsbservice]

Do the failed 2 machines ever recognise when you put stick in user mode? There are some cases front usb cable isn't plugged at the main board at the back.

[techsxge]

Check in settings if the machine accept usb. I think it was in Admin -> System Settings

[tulintron]

Check in settings if the machine accept usb. I think it was in Admin -> System Settings

+1

[mascan42]

Do the failed 2 machines ever recognise when you put stick in user mode? There are some cases front usb cable isn't plugged at the main board at the back.

Yes the port works under normal use. But even if there was no USB plugged into it, it should still give the dot in the corner when attempting to boot into firmware mode. This doesn't even get that far.

[tsbservice]

Yes the port works under normal use. But even if there was no USB plugged into it, it should still give the dot in the corner when attempting to boot into firmware mode. This doesn't even get that far.

Try it with front door open and unplug the LAN cable.