problem with new MikTex and new emacs installations

[Christopher W. Ryan]

I usually use Vince Goulet's modified emacs, containing AUCtex and ESS
and some other pieces, on Windows 7. It was version 24.5, 32-bit. Along
with an older version of MikTex 2.9 (pre-"MikTexConxole"), also 32-bit.

My MikTex 2.9 long ago lost the ability to install packages; would not
connect to the repository. It didn't bother me much because I had all
those I needed.

Today I installed the latest MikTex 2.9.7015, 64-bit. Regained the
ability to install packages. But also gained an error message when
compiling a LaTeX document with pdflatex in emacs: "LaTeX problems after
{x} pages" where x is the length of my pdf document.  Yet the resulting
pdf document looks fine.

Found this:

https://tex.stackexchange.com/questions/368408/auctex-says-latex-problems-after-1-page

about a change in date separator from slash to hyphen, so I installed a
new emacs, version 26.1 64-bit, from here:

https://vigou3.gitlab.io/emacs-modified-windows/

Using this new 64-bit setup, LaTeX files will not compile. Error reads:
"symbol's function definition is void Tex-function-p"

I still have my old MikTeX 2.9 32-bit and emacs 24.5 32-bit, in "Program
Files (x86)" in case that matters.

I am testing with a simple LaTeX source file:

\documentclass{article}
\begin{document}
Hello
\end{document}

Grateful for any suggestions.

--Chris Ryan