Wyse Z90D7: Updating 




BIOS update

Having tried several methods over the years I've ended up using the linux application flashrom. This is fine if you're planning to use your Z series as a Linux box, either with your own flavour of Linux or the Wyse variant. The Binary BIOS image is available from Dell's support pages, but only if you select ThinOS as the operating system.

However, if you are using (or intending to use) Dell's versions of Windows this may not be a good idea. I believe (tho' I haven't verified it) that an element of the Wyse/Dell Windows licence is built into the BIOS. If you update a box using the 'ThinOS' BIOS and then try and use one of the Wyse/Dell Windows builds you may have a problem. At least, with flashrom, you can save a copy of what was here to start off with and go back to the old version if necessary.

See Updating the BIOS for details.


[March 2019] Unfortunately Dell have now withdrawn support for old Wyse products and shut down the old Wyse support server: see here. As a consequence I've removed the old now dead links in the descriptions below but left the articles in place in case you may be able to track down the firmware elsewhere.

Firmware and/or BIOS update on a Z90

Unfortunately updating the firmware and/or the BIOS on a Wyse thin client is often not as slick as it should be. What you'll find here are three approaches to the problem. The first is one that I wrote back in February 2017 that describes how to go about updating the firmware and/or the BIOS using the standard Wyse tools. The second, contributed by Jouni from Finland in January 2019, describes an alternative approach for performing just a BIOS update. Then in July 2019 I tried out a different approach using a cheap USB programmer.


I wanted to update the BIOS of my Z90D7 but it turned out not to be a straight forward task - my first attempt being greeted by a 'Security Key' error thanks to the underlying change of the model hardware at some point. (See the firmware tab for further details). So I thought I'd start with reloading some standard firmware and move on from there. This is what I did...

The Starting Point

My Z90D7 has the part number 909587-02L. It's fitted with 4GB of flash and 2GB of RAM. It was manufactured in August 2011 and was running BIOS 1.0F. Whilst it was running Windows Embedded Standard 7 it looked like it was a generic installation of the operating system rather than a specific Wyse build. I couldn't see any mention of Wyse anywhere and the utility "Wyse Client Information.exe" was missing.

From my quick go at updating the BIOS it was obvious I needed to establish a proper base line as my starting point.

I already had V1.19.0.4 of the Wyse USB Firmware Tool that I had downloaded from

NB: If you need more detail about using the USB Firmware Tool I covered this here in the Wyse SX0 section.

The first step was to go to the [old Wyse support pages] and look at the downloads available for the Z90D7. One thing that was obvious was that all the current software is for hardware fitted with 8GB or 16GB of flash. My unit only has 4GB and so I moved on to the archive section.

Item 9 in the list of download options was BZB0_827_4096.exe. This was was the final image that should be compatible with my Z90D7 prior to applying the 2nd Generation Compatibility Kit upgrade. So a (lengthy) download of the 2.71GB package followed by a run of version 1.19 of the USB Firmware Tool created the pen drive update. I used a 16GB pen drive which meant the utility took a long time to run as it starts off by formatting the pen drive and it is remarkably slow in doing this. (Maybe I need to play again with the Windows compatibility settings?) In fact I could have got away with using a 4GB pen drive and saved a lot of time.

At this point I also downloaded item 7 - The 2nd Generation Compatibility Kit - ready to take the next step once I had Build 827 installed.

(Re)Installing Windows Embedded Standard 7

I plugged in the pen drive, reset the Z90D7, held the P key down to get the boot menu and booted the pen drive. The software duly ran and overwrote the flash, then updated the BIOS, and finally booted into Windows Embedded Standard 7. Another long wait (50 minutes?) whilst Windows Embedded started up and went through an extensive configuration process. Finally I had a definitive Wyse version of Windows Embedded Standard 7. Also the BIOS had advanced to 1.0L.

Installing 2nd Generation Compatibility Kit

The 2nd Generation Compatibility Kit is a ZIP file that contains a couple of read me files and three further compressed files, two of which are of interest to us. There is BZB0_BIOS_B02C0.exe and WES7_Flash.sys_C0.exe. Each of these expands to the typical Wyse file structure with a RSP file for use with the USB Firmware Tool

However, in the case of the 'Flash' one, we are just interested in the file flash.sys which we will install by hand. The other one we will use in conjunction with the USB Firmware Tool.

flash.sys: Copy this file onto a pen drive and then follow these steps:

  1. Start Windows on the Z90D7.
  2. Hold down the shift key on the keyboard and click on StartMenu->log off. Windows will then log off and display two 'logon' icons - Administrator and User. (Don't release the shift key until this appears).
  3. Log on as Administrator. You'll be prompted for a password which is Wyse#123. BEWARE: At this point Windows is likely to assume you are using a US keyboard. As I have a UK keyboard I need to type Wyse£123. i.e. The fifth character is shift/3 as that's where the # symbol is on a US keyboard.
  4. On the desktop click on FBWF disable icon to disable the write filter. If you don't do this any changes that are made to the filing system only happen in RAM and vanish when the system is rebooted. Having clicked on the icon the system will automatically reboot with the write filter disabled.
  5. Log off from the user and login as the Administrator again.
  6. Plug in the pen drive and copy the file flash.sys to C:\Windows\System32\Drivers
  7. On the desktop click on the icon FBWF Enable. The system will reboot as before.
  8. If you're paranoid you can log in again as administrator and confirm that flash.sys is now the new version.

Next fire up the USB Firmware Tool and select the options to push a BIOS image for Windows Embedded Standard 7. Then navigate to where the file BZB0_BIOS_B02C0.rsp is. This time I used a 2GB pen drive. Running in XP SP3 compatibility mode on my Windows 10 system it took just over 7 minutes to format the drive. After that it was maybe another 30-40 seconds to copy over the necessary files.

Next reboot the Z90D7 with the prepared USB drive plugged in. Hold down the P key as it starts up in order to get the boot menu.

In my case I found that it did not recognise the 2GB USB pen drive as bootable and it didn't appear as a boot option. I found this strange as the drives work perfectly if I set them up for Tiny Core. Anyway, as it is a long process to create a new image on a different pen drive, my solution to this was:

  1. Take a bootable pen drive that is set up with Tiny Core on it.
  2. Copy the contents of the Wyse pen drive over to the Tiny Core pen drive. (Essentially the directories grub, kernel, initrd and Image).
  3. Edit syslinux.cfg in the /boot/syslinux/ to add another entry:
    LABEL wyse
    MENU LABEL Wyse reimage
    KERNEL /kernel/vmlinuz
    INITRD /initrd/initrd.pxe
    APPEND  rw root=/dev/ram ramdisk_size=131072 vga=785 quiet splash=silent ide_generic.probe_mask=0x03
  4. Boot the pen drive and select that option from the menu.

The pen drive produced by the Wyse utility uses grub as the boot loader. The boot parameters can be found in the file /grub/grub.conf. All I did was take those parameters and alter them to suit the syslinux structure.

Anyway, however you do it, once the pen drive booted it went through the update process and I was now running BIOS 2.0C.

Note: I subsequently ran into the 'non-bootable USB drive' again after I'd loaded the final BIOS. It took a few minutes for me to realise what was going on.... Having loaded a new BIOS it transpired that that the 'Boot From USB' option in the BIOS had been reset to 'Disabled'. I advise you to have a quick look through the settings whenever you update the BIOS.

Final Update(s)

Returning to the Wyse archive download list we find item 2 - 0855_CommonStructure.exe - weighing in at a 2.82GB download. Here are a few highlights from the accompanying release notes:

....Minimum configuration 4GB Flash, 2GB RAM.

**** Please Note: This will be the last image that can be deployed to devices with 4GB flash size.  ****
**** Future images will require a minimum of 8GB.                                                   ****

-Builds can be pulled and pushed using Dell Wyse USB Firmware Tool or higher.
-To push to legacy Z and X devices with build numbers prior to build build 830,
 please update unit to build 830 and the 2nd_Gen_Compatability kit before attempting to
 deploy this image to those devices.

The following components are included/updated in this build:
BIOS     Common Bios (D/Z)    3.0D

-  The Image capture and deployment will not work with 4GB flash as the flash space is less than the
   recommendation. 	It's recommended to use 8GB/16GB flash for installation of additional software packages.
-  On 4GB flash, space left over after image deployment is approximately 360MB, depending on wireless module in use.
-  Due to the above, some devices will show the flash space in red due to reduced space. To remove this warning,
   uninstall unused applications.

So that looks like it is a goer and gets us as far as BIOS 3.0D. However the release notes do say under prerequisites: please update unit to build 830 so that's another download/flash cycle to be done - item 8 in the download section - BZB0_0830_4096.exe (2.70 GB).

FYI: Build 830 - 42 minutes to prepare a 4GB flash drive of which the first 35 minutes were spent formatting it. Watching paint dry is more entertaining.....

So I finished off by installing build 830 and the just updated the BIOS from the 0855_Commonstructure.exe download.

For the really dedicated you can try downloading item 1 in the 'Active' list (7.13GB!) and use the USB Firmware tool to just update the BIOS. (I haven't gone that far).

Take Two

In January 2019 I heard from Chris who, following the guide above, had upgraded the BIOS of his Z90D7. Here are some comments from his experience.

For the Wyse USB Deployment tool:

Thank goodness there is a big collection of Wyse Thin Client related tools at the address:"

When he got onto preparing/booting the USB pen drives:

It took me longer to get through this stage thanks I think due to degree of hardware dependency.

The USB pen drives I had to hand were a 16GB USB3 Kingston DataTraveler and an 8GB USB2 Toshiba pen drive.

Whilst it would boot quite happily on a more modern PC I could not get the 16GB Kingston DataTraveler to boot on the Wyse Z90D7. I tried both the 2.0 and 3.0 ports and also repartitioned the DataTraveler so that the boot partition was 4GB.

I had a similar experience with the 8GB Toshiba pen drive until I repartitioned it so that the boot partition was 4GB.

My conclusion is that, for updating devices such as the Z90D7, it is a good idea to use accompanying devices from the same era. If not you can end up wasting time trying to work out why they don't work as they should.


Any comments? email me. Added February 2017    Last update January 2019