FCD/FCD+ and Zadig – DON’T!!!


Increasingly recently we’ve been seeing problems where the symptoms suggest that folks have used a utility called Zadig to override the operating system’s own drivers, probably because there has been experience with an RTL dongle where it’s common to have to hack user-mode access to the device, overriding the device’s own drivers.

Fundamental to the FCD’s and FCD+’s design was to make it as easy to install as possible, and that means that it uses drivers that are native to your operating system so you don’t have to mess about fruitlessly searching the internet for the right driver, or, indeed use Zadig.

Using Zadig to override the operating system’s drivers for the FCD & FCD+ will not work!

What’s worse is that Zadig doesn’t appear to present a clean way to uninstall its own work from the investigations I’ve done, so getting you back to square one isn’t as easy as it was to install those pesky Zadig configured drivers in the first place.

In order to uninstall it’s a bit complex but here’s a recipe.

o Insert the FCD+ if it isn’t already.

o Look in your C:\Windows\Inf directory and look for all the oem*.inf files which relate to the FCD or FCD+. They are text files, so you can open them in notepad.

o Open an administrator command prompt and run “pnputil -f -d oem##.inf” for each oem##.inf file you found.

o In Device Manager, find entries marked “FUNcube Dongle V2.0 (Interface #)”, right click each and uninstall.

o Remove the FCD/FCD+.

o Now, after 10 or 10 seconds, reinsert the FCD+ and you should now have the device properly recognised. I recommend too that you take this opportunity to read the manual.

When properly working, the FCD+ presents a sound device (FUNcube Dongle V2.0), a human interface device (“HID-compliant device”), and under Universal Serial Bus controllers there should be a “USB Composite Device” entry for it. When properly configured, whn removing the FCD these three entries should all automatically disappear, and reappear when inserted.

If you still have entries in Device Manager in the form “FUNcube Dongle V2.0 (Interface #)” then you still have work to do to uninstall them.

Removing Zadig’s work is messy, time-consuming, and prone to possibly catastrophic errors if you remove the wrong driver.

So, to save yourself a whole lot of grief, the advice is simple: while you are welcome to use Zadig with your other devices, please DO NOT USE ZADIG under any circumstances to override the drivers for the FCD or FCD+!

Many thanks, Howard


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9 Responses to FCD/FCD+ and Zadig – DON’T!!!

  1. Randy says:


    I have been running both RLT and FCD+ on the same computer. I used ZAGIG to install the RTL drivers. Any issues with running both?

    Randy, K7AGE

    • admin says:

      Hello Randy

      I should have been more clear: I am not aware of any problems in them coexisting and running simultaneously on the same machine, but when configuring Zadig, only use it for RTL units and not for the FCD/FCD+.

      The problem arises from using Zadig to specifically override the FCD/FCD+ native drivers which is definitely not recommended!

      Many thanks, Howard

  2. John Lawson says:

    An observation on the Zadig Complication:

    I acquired two other, VHF+ dongles (one RTL2832 and one RT820 device) before getting the FCD+.

    So in the process of installing those, I ran Zadig and installed various other “.dll utilities” as prescribed by various users. In fact both dongles run as normal.

    Now, I see that I have painted myself into a digital corner. Note that I did not use Zadig to try and install the FCD+ , rather for that I followed your ample instructions… of course that process was doomed before it was begun.

    Now, to see if I can reverse the damage without any Unintended Consequences.
    I would much, much rather the Fun Cube ran well – the other two receivers could go to ‘good homes’ at that point. (They were cheap enough…)

    Once again, thank you for all your help!



    • admin says:

      Hello John

      Thank you for your note.

      In fact, to be clear, I believe it’s completely viable to coexist both RTL dongles run under a Zadig install and FCD/FCD+ devices. The trick is to resist configuring Zadig with the FCD/FCD+, and only configure your RTL devices with Zadig.

      Many thanks, Howard

      • John Lawson says:

        Greetings Howard –

        Just a quick note to say that I followed your procedures to ‘detox’ the FCD+ from the Zadig incursions.

        A bit tedious – but successful… my old ‘travel’ laptop running Vista is happily copying a 20M QSO via HDSDR as I type this.

        It took some figuring to determine just how one determines which of the “oemXX.inf” files applied to the FunCube – I managed to look for the VID/PID string in them.

        Also, quite a bit of (non-intuitive!) tweaking must be done to the several components of the system – but for me, once the several gains (including the “Recording Device” gain) were set, HF signals began to appear out of the noise.

        Thanks again for the support!

        One question: I would like to have a ‘decoder’ package, similar to TruTTY or Bonito, that would work in conjunction with HDSDR or the like, that I could use for TTY, PSK31, Packet, etc., etc., and the more ‘exotic’ data modes. Do you know of anything like this, or have any recommendations?



  3. Roger G4BBT says:

    Thanks for the info about Zadig. Unfortunately I fear I read it too late! I had my FCD+ running fine until I started looking at ‘plane plotter’ and at other adsb programs on http://www.sprut.de. I ran some downloads to try and get these applications going and seem to have run into the trouble you describe. Before I take any further steps to try and clear up the situation, would it help to go back to an earlier ‘restore point’ on windows 7. ?

    • admin says:

      Hello Roger

      Restoring to an earlier restore point may work, however it’s dependent on having an appropriate point to go back to!

      I am also adding one further step that I discovered last night while helping somebody else remove Zadig’s install, which is, after using PNPUTIL to remove the relevant OEM##.inf files, to right click and uninstall each of the FUNcube Dongle V2.0 (Interface #) entries in Device Manager.

      So, here are the steps:

      o Insert the FCD+
      o Locate the OEM##.INF files associated with the FCD+ by Zadig (these are readable text files in c:\windows\inf)
      o In an administrator command prompt, run “pnputil -f -d oem##.inf” for each of those OEM##.inf files.
      o In Device Manager, locate any “FUNcube Dongle V2.0 (Interface #)” entries, right click and uninstall them
      o Remove FCD+
      o Wait 10 or 20 seconds
      o Reinsert the FCD+

      When properly working, the FCD+ presents a sound device (FUNcube Dongle V2.0), a human interface device (“HID-compliant device”), and under Universal Serial Bus controllers there should be a “USB Composite Device” entry for it. When removing the FCD, these entries should all automatically disappear, and reappear when inserted.

      Many thanks, Howard

  4. serge szpilfogel says:

    I am running window Xp & have both dongles on a USB hub running Funcube dongle classic & RTL 820T. I have no problems RE: drivers settings. As Howard suggested install the driver for the RTL & leave the FDC unplugged et voila