Same issue as before (see below). I'll try another machine but I doubt it is that as I reinstalled the CLI already. Maybe the only recourse is to get a debugger (see Boron stuck in DFU mode) although I have no clue yet how to use it.
C:\Users\rober\Downloads>particle flash --usb tinker -v
dfu-util 0.8
Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2014 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to dfu-util@lists.gnumonks.org
Opening DFU capable USB device...
ID 2b04:d00d
Run-time device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Setting #0 ...
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 4096
DfuSe interface name: "Internal Flash "
Downloading to address = 0x000d4000, size = 11412
Download [=========================] 100% 11412 bytes
Download done.
File downloaded successfully
Transitioning to dfuMANIFEST state
Invalid DFU suffix signature
A valid DFU suffix will be required in a future dfu-util release!!!
Flash success!
C:\Users\rober\Downloads>particle flash --usb boron-system-part1@1.1.1.bin -v
dfu-util 0.8
Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2014 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to dfu-util@lists.gnumonks.org
Opening DFU capable USB device...
ID 2b04:d00d
Run-time device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Setting #0 ...
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 4096
DfuSe interface name: "Internal Flash "
Downloading to address = 0x00030000, size = 668192
Download [ ] 0% 0 bytesInvalid DFU suffix signature
A valid DFU suffix will be required in a future dfu-util release!!!
dfuse_download: libusb_control_transfer returned -9
Error writing firmware: Invalid DFU suffix signature
A valid DFU suffix will be required in a future dfu-util release!!!
dfuse_download: libusb_control_transfer returned -9
VError: Error writing firmware: Invalid DFU suffix signature
A valid DFU suffix will be required in a future dfu-util release!!!
dfuse_download: libusb_control_transfer returned -9
at Promise.resolve.then.then.then.then.then.then.catch.err (C:\Users\rober\AppData\Local\particle\node_modules\particle-cli\dist\cmd\flash.js:198:13)
at <anonymous>
at process._tickCallback (internal/process/next_tick.js:189:7)
caused by: Error: Invalid DFU suffix signature
A valid DFU suffix will be required in a future dfu-util release!!!
dfuse_download: libusb_control_transfer returned -9
at ensureError (C:\Users\rober\AppData\Local\particle\node_modules\particle-cli\dist\lib\utilities.js:670:14)
at Promise.resolve.then.then.then.then.then.then.catch.err (C:\Users\rober\AppData\Local\particle\node_modules\particle-cli\dist\cmd\flash.js:198:24)
at <anonymous>
at process._tickCallback (internal/process/next_tick.js:189:7)
C:\Users\rober\Downloads