[Update] ESXi-Customizer-PS 2.5 - The ESXi image customization script

This is just a quick heads up for the users of my ESXi-Customizer-PS script for ESXi image builds and customizations. I have just published the new version 2.5 of the script, and that adds
  • full support of vSphere 6.5 (use the new -v65 switch to limit Image profile selection)
  • support of PowerCLI 6.5
  • enhanced logging capabilities
If you have run into issues with older versions of the script then please update now and let me know how it goes.

In the meantime VMware has also published the ESXi 6.5 GA bits to its Online Depot, and that means it is very easy to create an ESXi 6.5 installation ISO or Offline bundle with my script. Just run it without any arguments for the ISO file (or only the -ozip switch for the Offline Bundle), and it will do its magic.

Have fun!

This post first appeared on the VMware Front Experience Blog and was written by Andreas Peetz. Follow him on Twitter to keep up to date with what he posts.


  1. Starting with esxi 6.5 load net-tulip is no longer working. This esxi version has issue loading this nic driver

    .\ESXi-Customizer-PS-v2.5.ps1 -v65 -vft -load net-tulip
    install using the customize 6.5 iso can't detect this nic. The vmkernel.log shows

    Elf : 2219: Load of failed : missing required namespace :

    I don't have issue doing this for vsphere 5.5 or 6.0

    1. Hi Phong,

      I'm sorry, but this driver is incompatible with ESXi 6.5, because it was compiled using the source code of ESXi 5.0 only. I have updated my related article accordingly: ESXi 6.5 Release Notes for free license and white box users.


  2. Welche PowerCLI Version ist erforderlich, um die Images für eine gegene Hyervisorversion fehlerfrei zu bauen?

    1. Das hängt nicht von der ESXi-Version ab. Wie auf der Projektseite beschrieben sollte das mit PowerCLI 5.1 oder neuer funktionieren.

  3. A minor suggestion, when your script is run under PowerShell ISE it always generates meaningless error messages when it tries to resize the window.
    It would be nice if that wasn't the case, for instance checking that $newsize is valid after setting to windowsize works.

    $newsize = $pswindow.windowsize
    if ( $newsize ) {
    if ( $newsize.height -lt 50)...
    if ( $newsize.width -lt 120)...
    $pswindow.windowsize = $newsize

  4. An unexpected error occured:
    [WinError 10054] An existing connection was forcibly closed by the remote host
    How to fix this issue?

  5. Hi, i experienced the same issue. Managed to fix it as i was experiencing issues with Rufus SSL message. This lead me in the right direction


    Download the easyfix at the bottom

  6. Dear Andreas,

    I want to thank you for all the work you have put to this tool. It is amazing, and it works perfectly with the images provided from VMWare.
    I wanted to ask you if there is a way to use a customised version of a vendor and include the net-tulip drivers. I tried with one from Dell (https://www.dell.com/support/home/be/fr/bebsdt1/drivers/driversdetails?driverid=21wny) but it doesn't seem to work. I might be using a wrong iso file or I might be misreading some part of your guide. Any advice on this?
    Thanks in advance, Nikolas

    1. Hi Nikolas,

      you can also add custom drivers to vendor ESXi images. You just need to have it available in Offline bundle (ZIP) format and can then use it with the -iZip switch.

      ISO files cannot be used as an input to the script.

      The Dell customized images of newer ESXi versions are also available in ZIP format. E.g. for 6.5 here. ESXi 5.1 is just too old and out of support. You really shouldn't use that.



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