Windows 11 25H2 (build 26200) not recognised as supported platform

[mickey-mikey]

Description

Running any MiKTeX tool (e.g. pdflatex) on Windows 11 25H2 produces:

pdflatex: critical issue: You are running MiKTeX on an unsupported version of Windows.
pdflatex: major issue: So far, you have not checked for MiKTeX updates.

Compilation works correctly despite the warning. Per the MiKTeX prerequisites page, the supported platform is "Windows 11" with no build restriction, so Windows 11 25H2 should be supported.

Environment

• MiKTeX version: 26.1 (latest, all packages up to date)
• OS: Windows 11 Pro 25H2, build 26200.7840
• Architecture: x64

Steps to reproduce

1. Install MiKTeX 26.1 on Windows 11 25H2
2. Run any command, e.g. pdflatex --version or compile any .tex file
3. Observe the "critical issue" and "major issue" warnings in stderr

Expected behaviour

No platform warning, consistent with the documented prerequisites.

Notes

• Windows 11 25H2 (build 26200) is the current general availability release, not an Insider/preview build.
• miktex packages update reports no updates available, so the "have not checked for MiKTeX updates" message is also incorrect.

[edocevoli]

I was not able to reproduce it on a 25H2 system. pdflatex --version shows no error message.

[mickey-mikey]

@edocevoli I think I've tracked this down to a stale issues cache from an in-place upgrade.

My initexmf --report shows:

SetupVersion: 24.1
SetupDate: 2025-11-15 10:18:00
CurrentVersion: 26.1

I originally installed MiKTeX 24.1 and later updated packages to 26.1. The package update upgraded the binaries but never re-ran FindIssues(), so %APPDATA%\MiKTeX\miktex\config\issues.json still contained the stale warning from the 24.1 setup, which had flagged build 26200 as unsupported.

Running initexmf --report triggered a re-evaluation with the 26.1 code, which correctly sees 10.0.26200 as supported and cleared the cache. The warning is now gone.

It looks like mpm --update / package updates don't invalidate or re-run FindIssues(), so cached warnings persist across version upgrades.

[mickey-mikey]

@edocevoli, sorry I'm less certain now. I'm unable to reproduce it via the upgrade path. I'll keep investigating and post back here if I have any luck.

[mickey-mikey]

What I can confirm:

• The warning was cached in %APPDATA%\MiKTeX\miktex\config\issues.json and served by AutoDiagnose() in app.cpp
• Running initexmf --report triggered FindIssues() which re-evaluated, correctly passed IsWindows10OrGreater(), and cleared the cache
• I tested clean installs of 24.1, 25.12, and 26.1 on the same build 26200 system — none of them generate the "unsupported platform" entry
• VerifyVersionInfoW consistently returns true for the >= 10.0 check on this system
• The workaround is initexmf --report (or waiting up to a week for AutoDiagnose() to refresh the cache)

What I can't explain: what originally caused IsWindows10OrGreater() to return false and populate the cache

[github-actions]

This issue has been marked as stale due to inactivity.

[github-actions]

This issue has been automatically closed due to inactivity.