Intro. to Zadig

Introduction to Zadig


Some OpenTX users have reported difficulty using USB3 ports to communicate with OpenTX Companion. It seems to depend upon what chipset your machine uses. Several methods were tried to alleviate this problem, and finally Zadig was found to be the apparent solution. 
If you follow the steps in this lesson exactly and you still can't make things work, check to see if you have the latest version of Zadig installed. You must have v2.1.0 or later. You can download the latest version of Zadig from HERE.
If you have the latest version of Zadig, try changing to a USB2 port, if available.  The alternative is a USB3 port.  USB3 is the newer version, and is usually indicated by having a blue insert/guide that is visible when looking at the port.

Note:  Please click HERE for a downloadable copy of the Using Zadig Checklist and Notes.


If you’ve hung out in any of the forums at all, you’ve probably heard, and perhaps been alarmed by, the apparent difficulty that some users have when initially trying to update to OpenTX firmware for the first time. It’s probably the single most feared, confusing, and frustrating thing about OpenTX, and has brought more than one enthusiastic OpenTX neophyte to their knees. We’re going to get you through it, hopefully with as little anxiety as possible. The basic difficulty seems to be that Windows does not install the proper driver to allow OpenTX to communicate with the main STM chip in the radio. Until that happens, the operating system doesn’t recognize the chip, and you’re dead in the water. Don’t worry! You’ll be shown where and how to download and install the driver and get your machine talking to your transmitter. Mac and Linux computers use a driver called: dfu-util-0.7.mpkg.

Lesson Goals

There’s only one goal in this lesson, and that’s to get your computer communicating reliably with your Taranis. Nothing happens without that.


In this day of Plug-n-Play, we’ve become used to simply connecting a new device, having the computer recognize it, install the appropriate driver, and we’re ready to go. Sometimes this doesn’t happen. This is one of those times. We would like to use a different driver when working with OpenTX Companion and the Taranis. This driver is not included in the normal Windows driver package, so you have to go out, get it and install it on your machine. You do that with a little program called Zadig. Scary? For many of us, of course! Impossible? Absolutely not!

Lesson Progression

Read and understand the information above. Know why we’re doing what we’re doing. Download and print the discussion notes and lesson checklist from the link at the top of this page . There is also a link at the top of the next page, “Using Zadig.”  At least look them over. My feelings will be hurt if you don’t. Finish this page, then move on to the next lesson: “Using Zadig.” Watch Scott Page’s latest video, OpenTX 2.0 and Beyond: Come Join the Party!, on how to upgrade a Taranis (not Taranis Plus) from a pre-v2.0 version of the firmware to v2.0.12.  The techniques and examples that he shows are identical to what’s in the lessons.

NOTE: If you have a Taranis Plus, see the comments section (below).

Follow the steps in the checklist  to see if you already have a working STM32 BOOTLOADER installed. Chances are, if you’ve been flashing different versions of OpenTX, you’re set to go. If you’re on a Windows machine and this is the first time you’ve attempted this, you’ll probably have to download and install Zadig. Use the images in the checklist and the videos as references as you move through the process.


PLEASE, let’s not get into a discussion about which computer platform is best, or, “Well, if you had MY computer, you wouldn’t have to do that!” That’s like discussing politics or gun control at a cocktail party. You’re not going to change any minds, and all you’ll do is ruin it for the host. Let’s just accept that there are differences and we all have the option of making our own choice.


Intro. to Zadig — 11 Comments

  1. Hi. I am all noowbie to opentx. :/ I just got my taranis plus from last week and i am trying to figure out the whole (confusing) Taranis story. The confusion mainly because I have a “plus” and all information/videos online relate mostly to the original Taranis. It took me some time to figure that out, and it only became clear after reading this page. My Taranis plus came with firmware So now I tried to download OpenTX companion 2.0.17 and i ran into this problem…. Any ideas why Norton gives me a virus warning on the open tx companion 2.0.17 ? It automatically removed the file saying it was a WS.Reputation.1 threat. I’m unsure whether to disable norton as the 2.0.15 download seems to be clear of threats. Can a virus slip in during download time and time again only on that same file, or is this a fake warning?? Tks

  2. “Using Zadig.” Watch Scott Page’s latest video on upgrading a Taranis (not Taranis Plus) from a pre-v2.0 version of the firmware to v2.0.12.

    I have a Taranis Plus – What “upgrades” are required for this version of Taranis?

    • Hi! Thanks for stopping by.

      The FrSky version that ships on the radio is a perfectly serviceable firmware, but the Developer’s version that’s discussed on this site has enhanced features that you might find useful. You only need to upgrade/update if you wish to move away from the FrSky version of OpenTX and join our happy band of Developer’s Users.

      At this time, OpenTX (the Developer’s version, not the one that comes on your radio from FrSky) is currently distributing v2.0.12. That version applies across all platforms that use OpenTX v2+, including both the Taranis and the Taranis Plus. You just have to select the flavor you want!

      Also, you don’t need Zadig to upgrade your Taranis Plus! The upgrade procedure for the Plus is much easier. Try this and see if it works. I’m going to assume that you have Companion installed on your computer. If not, my very strong recommendation would be to do so. This method will not work without it.

      1. Open Companion.
      2. Download and save v2.0.12 of OpenTX for Taranis Plus. Be certain that you change the radio type in Settings –> Settings from the main Menu Bar in Companion before you do the download. The default is the Taranis, not the Taranis Plus.
      3. Start your T+ in bootloader mode by holding both horizontal trim switches to the inside as you turn on the TX.
      4. Connect your TX to your computer via the USB port on the back of the TX. Pause a moment to be certain that it’s recognized.
      5. Click either the “Read Firmware from Radio” icon in the Companion toolbar OR select it from the Read/Write drop down menu at the top of the Companion window.
      6. Download and save the existing firmware.
      7. Click “Write Firmware to Radio”, navigate to wherever you stored v2.0.12, and select it.
      8. Select any special splash screen you wish to use, then click: Write to TX.
      9. That should do it. Unfortunately, after the operation completes, there’s no indication that it’s through. You’re returned to the blank Companion screen.

      Try that and see if it works for you. If it doesn’t, drop on back.

      Take care!

      Leonard (mac44mag)

      • Didn’t work for me, still won’t connect to my T+ even in bootloader mode 🙁

        Device Manager shows the device connected correctly without error.

  3. On this page under ‘Lesson Progression’ it says to watch both of Scott’s Videos. I of course know they mean Scott Page and his great work. But it has no link to them or any mention of the titles so I can search for them myself.

    Also it says this: Download and print the discussion notes and lesson checklist. At least look them over. My feelings will be hurt if you don’t.

    HUH? What are discussion notes and where are they? and where is the lesson checklist? Sorry but I am trying to do this front to back reading everything but I don’t know about the stuff above.


    • Hi, Marty!

      There are links to the Using Zadig checklist at the top of both this page and the next one. The links to the videos are also on the next page. I’ve changed the verbiage a bit to hopefully make their location a bit more clear.

      Thanks for stopping by!

      Leonard (mac44mag)

    • When you start Zadig, do you have your TX connected to the computer with the power OFF? If not, that’s the place to start. If not, check back.

      Sorry for the delay in responding.

      Leonard (mac44mag)

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