Installing the EasyFlash 3 Driver in Windows 10

I finally decided to purchase an EasyFlash 3 cartridge from RETRO Innovations.  As is typical the documentation was nonexistent, so it was time to dig and figure out how to load .crt images onto the cartridge.  Didn’t take me long to find this website.  All the directions seemed easy enough, obviously the first thing that I needed to do was get the drivers installed, which is detailed on this page.  If everything had gone as documented I would not be writing this post!

Following the Directions (sort of)

Plugging in the EasyFlash did not bring up a driver installation dialog it just auto installed something unspecified.  I figured I would check the Device Manager to see what it had done and if it was anything close to correct.

Well I don’t know what correct is, but this is very likely not correct.  Ok, well I will download the driver from here and update the driver by hand.  Once the drivers are unzipped somewhere, I just put them in “Desktop\EF3-driver-windows”.  Right click the EasyFlash 3 device in the Device Manager and select “Update Driver Software…”.

Select a “Browse my computer for driver software”.

Navigate to where you downloaded the driver, click “Next” and that should be that!

Swing and a miss!  This error message came up.

Ok if you have ever dealt with Windows 10 drivers you know now a days every driver has to be digitally signed for “security” and Windows no longer lets you install unsigned drivers at all.  Well this is very bad news.

What Now?

Searching the internet I found this post.  This lead me to this post on how to disable driver signature verification.  For me this was a non-starter, for a variety of reasons, so what are my other options.  I happen to notice the below image on the driver install page.

The image shows that the EasyFlash 3 is a “libusb (WinUSB)” device.  Lately I have been dealing with the intricacies of the ZoomFloppy, which is story I will tell in a separate post.  With the ZoomFloppy you have to use a third-party tool to install a signed libusb-based driver.  The tool also allows for the installation of a signed WinUSB driver.  Lets see if we can make it work!

Trying Zadig

The driver installation tool is call Zadig and can be downloaded from here.  So I downloaded and ran it.

It recognizes that the EasyFlash doesn’t have a driver.  So I select the “WinUSB” driver and hit “Install Driver”.  Lets check the Device Manger again.

This looks promising!  So I hooked it all and tried transferring a crt image as described here.

SUCCESS!!  So there it is.  How to install the EasyFlash 3 driver in Windows 10 without disabling driver verification.  Any questions, just let me know.


Something witty! I'm a full-time software engineer, part-time streamer, PhD, RetroSpy developer, bipolar, Ultima fanboy and a video game hardware collector.

16 Replies to “Installing the EasyFlash 3 Driver in Windows 10

  1. A very late reply:

    You can actually have Windows install it without using any .inf files.

    Go to device manager, right-click on the EasyFlash device, and select Update Driver. Then choose to Browse for drivers, and “Let me pick from a list…”

    From there, choose Winusb device, and click Next. Say Yes to the warnings, and you’re done. The device is installed, no weird 3rd-party signing packages needed.

  2. (Same situation) Unfortunately tried bypassing digital signature and still needed complained on needing one. Then, with this method I also tried setting it up as WinUSB (Successfully), but still EasyFlash 3 did not recognize the FTDI connection.

    Any thoughts for possible issues or debugging…
    Using Windows 10, and I validated all EF3 prerequisites

    1. Well I can definitely repro the problem. Newest version of Win10 and I cannot upload anything either. I will look into the problem and see what I can find.

    2. What did you get in the programming window. Was it:
      Send PRG file: Filename.crt
      Send command: EFSTART:PRG

      or was it:
      Send PRG file: Filename.crt
      Send command: EFSTART:PRG
      Got response: “WAIT”.
      Send command: EFSTART:PRG
      Got response: “LOAD”.
      (LOAD) Start to send data.


      I am getting both and once it actually programmed the file.

      1. Just caught your responses, sorry as well for late reply. I reverted to using a Windows 7 machine and going well, but would like to resolve on this Windows 10 machine…

        The message in EasyTransfer window is as follows:
        Send CRT file: C:\…\…\…\filename.crt
        Send command: EFSTART:CRT
        Unable to open ftdi device: -4 (usb_open() failed)
        Write failed: 0 (usb_open() failed – unknown cause)
        It is the FTDI that fails….(never connects), eg without connecting, cannot remotely run EasyProg on C64

    3. One more question. When you do try does anything happen on the C64? nothing happens in the first case and in the second case it goes to a blank blue screen. I am just trying to see if I can repro your issue.

      1. Nothing on C64 happen, stuck on just connecting (FTDI error). The menu only can be up, or I manually run EasyProg to kick start it, no screen blanking, etc..

    4. Also have you tried the command line tool in the easytransfer folder? Running the command line it worked everytime, in the GUI it was really hit or miss.

      1. I will give this a try, however not confident that this will resolve the issue.
        Between both Win 8.1 and Win 10 machines, I use the same USB cable. The Device Manager references both EasyFlash 3 devices under Universal Serial Bus device
        Win 8.1
        Shows on Port_#0001. Hub_#0001
        Device configured, started, installed
        Win 10
        Shows on Port_#0002. Hub_#0001
        Device not migrated (first). Then, shows Device configured, started, installed
        Looking at the details of the message I see…
        Title: Driver Management concluded the process to install driver easyflash_3.inf_amd64_412bb73193ecfcd3 for Device Instance ID USB\VID_0403&PID_8738\08-15 with the following status: 0x0.
        Device USB\VID_0403&PID_8738\08-15 was not migrated due to partial or ambiguous match.

        I assumed this was because I had both AMD and x86 folders with ambiguous drivers and it errored on the AMD. Then resumed and completed on the x86

        Assuming something may have been wrong there, I removed the AMD driver from the folder, uninstalled and will install again.

        I’ll have to post a separate update, as I’ll have to reboot this laptop first.

  3. Removing the AMD co-installer only prevented the Driver from being updated….Oh… A shot in the dark, but it’s the thought that counts….

    Issue remains Win 8.1 is OK, Win 10, driver installed, but FTDI not working on EasyTransfer attempt.

  4. Send PRG file: D:\Program Files\C64\Gry\Boulder Dash.d64
    Send command: EFSTART:PRG
    Got response: “WAIT”.
    Send command: EFSTART:PRG
    Got response: “LOAD”.
    (LOAD) Start to send data.
    USB operation failed: -1 (usb bulk write failed – Operation not permitted)

  5. Thank you for helping out the people with these instructions. As you know the EF3 was/is just a hobby project for me and I didn’t have time for it in the last years. It seems this becomes better now (maybe because it’s not easy to do many other things nowadays :/), so I could update the instructions on the main EasyFlash Website. Thanks again for writing this here!

  6. Same issues for me in W10, though usb device was installed with Zadig. I tried in every way but I refuse to reprog cart with tons of high specialized progs, SKOE… Sorry but I’m really disappointed with EF3, it should be clear it’s not a user-friendly device for a mid grade C64 user. Note I can use and easily program 1541 ultimate, Tc64, and connect my c64 to lan through mmc replay and rrnet but not to be able to simply let recognizable EF3 to W10(!).
    Ok it’s a free project and I appreciate your great competence but
    summing up: Beatiful piece hw, high possibilities but … unripe project.

  7. I have had mixed success with my EF3. Some of it my own fault for trying to perform flashing on a compromised C64. Knowing now that I have two working machines available, I wanted to reflash a slot today. The Easy Transfer program is the most convenient option for me since I do not have large enough storage. I received an error I had not seen before. It is the same as Prospero’s above. What has changed since the last time I used it successfully? Windows 10, perhaps. Critical Updates are a monthly occurrence. Just in case the driver was somehow damaged, I uninstalled and reinstalled. Same error. I also replaced USB cables. Sigh.

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