Help needed with compatibility issue

[Jürgen Spitzmüller]

Am Freitag, dem 04.09.2026 um 19:01 -0700 schrieb Joe Maxwell via lyx-
users:
> I've been using LyX for ca. 5 years and just yesterday ran into a
> major issue for the first time. I have ca. 1200 pages saved in LyX
> 2.3.2. files, have not upgraded my version (and won't until all the
> bugs are ironed out). BUT: every time I try to open any of these 8
> files, I receive the following message: 
> "[FILE NAME] is from a newer version of LyX and the lyx23lyx script
> failed to convert it."
> WTH?! I've used the same version of LyX for years and have never had
> a problem. Now I cannot open any of the files! 
> Has anyone experienced this and does anyone know how to fix it?

Can you post the very first lines of (one of) these files when you open
them in a text editor?

I am interested in something like

#LyX 2.5 created this file. For more info see https://www.lyx.org/
\lyxformat 643

-- 
Jürgen