LaTeX forum ⇒ General ⇒ Problem with article.cls after installing lyx

[roishik]

Hi,
I just install the updated version of Lyx on my Windows 10. I didn't change any of the default settings, but yet - the program don't compile well.
When I activate the program I see the following message:

The selected document class Article (Standard Class) requires external files that are not available. The document class can still be used, but the document cannot be compiled until the following prerequisites are installed: article.cls

does anyone knows what's the problem?
I couldn't find a good explanation for the problem anywhere.
what should I do?

Thanks!

[Stefan Kottwitz]

Hi Roishik,

welcome to the forum!

Do you get any other error message? Can you please post a .log file for the LyX/LaTeX run?

Stefan

[tuulip]

I have the same problem, I hope someone could help.

Recently installed Lyx 2.2 on Windows 10, and now I cannot open my old Lyx files. Upon opening a previously created and working file, I get the same error message as shown above, for article.cls as well as natbib.sty. Same thing if I try opening a template like beamer, warns of several missing class/style files (beamer.cls, amssymb, hyperref, pgf, xcolor, xxcolor).

Two issues:
1) I have installed the files I found from MikTex (2.9), e.g. beamer, natbib etc etc., and reconfigured Lyx after that, but nothing changes.

2) I don't even see an article.cls in MikTex, so how could I install it? I installed koma-script package, is that it?

If you need to see a log file then please advise how to get it.

Many thanks for all your help!

[tuulip]

Searching for info on this problem, I found some advise suggesting to go to miktex settings and change "install missing packages on the fly" to "no". This has no impact on the problem whatsoever. (Also tried the standard restarting of the computer - no effect.)

[Stefan Kottwitz]

Hi tuulip,

welcome to the forum!

Install the ltxbase package using the MiKTeX package manager. It contains the base classes, such as the missing article.cls.

"install missing packages on the fly" is actually a good feature, I would re-enable it. Disabling was a workaround for an issue with a TeXnicCenter editor version. The best though, is to install a complete MiKTeX (or complete TeX Live) right at the beginning, this saves such headache later.

Stefan

[CornerSolution]

I had the same issue, and none of the posted solutions fixed the problem (the necessary packages were already shown as installed in MiKTeX). I finally solved the problem, so figured I'd post what worked for me in case anyone else comes across this.

The solution was as simple as selecting Tools -> Reconfigure in LyX. Give it a minute until it says it's finished, then restart the program. The error/warning messages disappeared for me after that.