after running a MiKTeX-x86 update today, biber can no longer be called. I have found a number of issues like that from several years ago, but nothing with this specific error... in fact, this error doesn't seem to appear anywhere.

Running biber results in a message saying "biber failed" from the wrapper in miktex\bin\biber.exe, the log file miktex\log\biber.log contains the following:

INFO  biber - this process (2664) started by powershell in directory .... with command line: "C:\Program Files (x86)\MiKTeX 2.9\miktex\bin\biber.exe"
FATAL biber.core - The program '{name}' could not be found.
FATAL biber.core - Data: engine="exe", path="executables/windows-x86/biber/biber.exe", name="biber"
FATAL biber.core - Source: Libraries\MiKTeX\Core\Session\runperl.cpp:57

According to miktex/config/package-manifests.ini, the correct path for the installed binary is texmf/biber/bin/windows-x86/biber.exe. This file exists, and can be called manually:

PS C:\Program Files (x86)\MiKTeX 2.9> biber\bin\windows-x86\biber.exe --help
    "biber" - A bibtex replacement for users of biblatex

I have tried so far (with no change):

  • refreshed the FNDB
  • removed the FNDB and regenerated it
  • uninstalled, verified file locations and reinstalled biber

Assuming the miktex wrapper is serious about path="executables/windows-x86/biber/biber.exe", a path like that does not exist anywhere so I'm not surprised it can't call it. UPDATE: might be a packaging issue for this native package, all other platforms do use executables/....

What's going on here?

(To be able to get anything done today, I've replaced the wrapper with a hardlink to the true binary and that works, but ideally I'd want to fix my installation.)

Additional Information:

  • Packages updated: babel-french cjk l3kernel l3packages lineno ltxbase miktex-misc oberdiek pdfpages platex polyglossia pstricks setspace (can't see anything related)
  • Update in Admin mode, and I make sure to always only install packages in the "Common" root (the auto-installer is configured to ask for elevated permissions)
  • 1
    Just because it always comes up, how exactly did you update miktex? Do you have both user mode and admin mode in your miktex? If so, did you fully update in both?
    – daleif
    Jan 16, 2023 at 11:35
  • @daleif Admin mode only, and I make sure to always only install packages in the "common" root (the auto-installer is configured to ask for elevated permissions). Just to be sure I've checked, and nothing else comes up. My user root is basically empty except for some caches.
    – Martok
    Jan 16, 2023 at 11:45
  • works fine here, but I have a single user installation in my user account. Such problems should be reported at the miktex github tracker, but I would at first check the pathes, and not call biber from C:\program files, but in a user document folder. Jan 16, 2023 at 12:08
  • I cannot reproduce this on my MikTeX installation (updated a few second ago, multi-user, all packages installed as Admin, Win 10). My MikTeX bin directory is in the PATH though so that I can easily call just biber and don't have to mess with the whole file path.
    – moewe
    Jan 16, 2023 at 14:23
  • Hope something happened while installation, better to download and install again in Admin mode
    – MadyYuvi
    Jan 16, 2023 at 15:13

1 Answer 1


"Works as intended".

Apparently MiKTeX dropped support for x86 without any notice to existing installations. You can even still update everything and install new packages, it just will randomly brick (parts of) your installation.

Github: https://github.com/MiKTeX/miktex-packaging/issues/315

Time to reinstall everything then.

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