# gSender Flashing Issue **URL:** \ **Category:** ❓ Question\ **Created:** [July 15, 2026, 7:27pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727 "2026-07-15T19:27:10Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 15, 2026, 7:27pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/1 "2026-07-15T19:27:11Z")
Trying to flash firmware onto new laptop. Get this error message. “Error: Unable to find valid device using vendor ID “483” and product ID “df11”. Make sure the device is in DFU mode. Error: [object Object}” What does this mean and how do I proceed? Thanks in advance. ---
**Author:** ![Chucky\_ott](https://forum.sienci.com/user_avatar/forum.sienci.com/chucky_ott/32/8692_2.png) [@Chucky\_ott](https://forum.sienci.com/u/Chucky_ott)\ **Post date:** [July 15, 2026, 8:23pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/2 "2026-07-15T20:23:33Z")
@Spiritrunner To clarify, you’re trying to flash the controller and not gSender, right ? DFU Mode stands for Device Firmware Update Mode Instructions are here: [Firmware & Flashing - SuperLongBoard](https://resources.sienci.com/view/slb-firmware-flashing/) You can’t flash over ethernet so if you’re using that, you’ll need to switch to USB ---
**Author:** ![Altmillal1114](https://forum.sienci.com/letter_avatar_proxy/v4/letter/a/f6c823/32.png) [@Altmillal1114](https://forum.sienci.com/u/Altmillal1114)\ **Post date:** [July 15, 2026, 11:59pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/3 "2026-07-15T23:59:27Z")
You need to install drivers. Follow the steps here > **[Firmware & Flashing - SuperLongBoard](https://resources.sienci.com/view/slb-firmware-flashing/)** > > Page Suggestions? Check Firmware Version Your board will likely ship with the latest firmware already installed, but we occasionally make updates to add new features or address any discovered issues. You may also choose to re-flash the firmware onto... ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 16, 2026, 1:13pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/4 "2026-07-16T13:13:16Z")
Thank you for the responses. So I will need to download and install the [STM32Cube File](https://drive.google.com/file/d/1XzT21kwJFHcPzCDYhIdux49At6-TmrVA/view?usp=drive_link) to complete the flashing process? ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 16, 2026, 2:50pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/6 "2026-07-16T14:50:04Z")
When I open gSender all controls are grayed out. The program states I’m connected to the controller. (Com3, grblHAL) When I check to see what firmware version is running on the machine information screen, that info is blank. The field does not exist. I believe I am following the instructions that were given to me. Your thoughts on the issue ---
**Author:** ![Chucky\_ott](https://forum.sienci.com/user_avatar/forum.sienci.com/chucky_ott/32/8692_2.png) [@Chucky\_ott](https://forum.sienci.com/u/Chucky_ott)\ **Post date:** [July 16, 2026, 3:41pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/7 "2026-07-16T15:41:00Z")
@Spiritrunner it might help if you let us know which machine and which controller you have. New problem on an existing machine that had been working, or new machine you are setting up for the first time? I’m guessing a comms issue between gSender and the controller. Has the eStop has been disengaged (Press, turn, release. Two lights turn on) ? Have you tried a new USB cable ? Have you tried Ethernet instead of USB? ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 16, 2026, 7:17pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/8 "2026-07-16T19:17:59Z")
Thanks for responding. History: Have had a 48x30 SLB since fall of 2023. The ancient laptop I used to operate it finally died. Had an LG Gram I hooked up a month ago using gSender 1.6.0. No luck. Moved to 1.5.1 as others who had the same issue did. Again no luck. Currently trying to use 1.6.2. As I said earlier when it first loads it connects on COM3, grblHAL. Status is disconnected, the stop icon is active. All other controls are grayed out. The machine information says “Firmware Version: 1”. I feel I need to reflash. When I do that I get the message “Unable to find STM device in DFU mode after6 seconds. Make sure the device is in DFU mode, then try again.” So it appears I need help putting “the device” in DFM mode. As this is totally out in left field for me, I need step-by-step instructions. where do I look. And again thanks for responding. ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 16, 2026, 7:22pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/9 "2026-07-16T19:22:23Z")
PC is running Windows 11 ---
**Author:** ![Chucky\_ott](https://forum.sienci.com/user_avatar/forum.sienci.com/chucky_ott/32/8692_2.png) [@Chucky\_ott](https://forum.sienci.com/u/Chucky_ott)\ **Post date:** [July 16, 2026, 7:25pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/10 "2026-07-16T19:25:09Z")
@Spiritrunner Have you tried a different USB cable? Some of them are charging cables only. Or try with ethernet ([Technical Manual - SuperLongBoard](https://resources.sienci.com/view/slb-manual/#usb-amp-ethernet)) Unless something happened to your SLB since moving to the new computer, a firmware upgrade should not be needed for any version of gSender to connect. ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 16, 2026, 7:28pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/11 "2026-07-16T19:28:49Z")
Using the same cable that always worked. The controller hums when click connect so I feel it OK. Its also the only cable I have works connecting the pc to the longmill. ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 16, 2026, 7:35pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/12 "2026-07-16T19:35:33Z")
Console says “Connected to com3 with a baud rate of115200” ---
**Author:** ![Chucky\_ott](https://forum.sienci.com/user_avatar/forum.sienci.com/chucky_ott/32/8692_2.png) [@Chucky\_ott](https://forum.sienci.com/u/Chucky_ott)\ **Post date:** [July 17, 2026, 12:11am UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/13 "2026-07-17T00:11:59Z")
@Spiritrunner I got nothin’ more for you except maybe this: [Power and Connection – Sienci Labs](https://sienci.zendesk.com/hc/en-us/categories/38747234767892-Power-and-Connection) ---
**Author:** ![Spiritrunner](https://forum.sienci.com/letter_avatar_proxy/v4/letter/s/a87d85/32.png) [@Spiritrunner](https://forum.sienci.com/u/Spiritrunner)\ **Post date:** [July 17, 2026, 12:22pm UTC](https://forum.sienci.com/t/gsender-flashing-issue/26727/14 "2026-07-17T12:22:28Z")
Chucky\_ott, thanks for your time and effort!