MiKTeX and proTeXt ⇒ Writing grapics to file for later inclusion

[TonyK]

I'm new to this forum so please cut me some slack while I learn the ropes.

I have a lot of tikz graphics in my document and I'm trying to use the Latex feature that writes the graphics to an external pdf file for inclusion on later compiles to save recompiling them on every run. I have the following relevant lines to the preamble:

Code: Select all

\usepackage{pgfplots}
\usepgfplotslibrary{external}
\tikzexternalize
\pgfplotsset{compat=1.18}

and I've added the following to the command line call to pdflatex: pdflatex -shell -escape myfile.tex (BTW, I tried this without the word pdflatex and get the same result.)

The file compiles but I get the same error on every graphic -- essentially, sorry, the call to pdflatex did not produce a usable file myfile. The home directory contains three files for each attempt:
myfile-figure#.dpth,
myfile-figure#
myfile-figure#.md5

What am I doing wrong? Also, and I don't know if this is related to my issue, I keep getting the message:

pdflatex: major issue: So far, you have not checked for MikTex updates.

[TonyK]

I forgot to mention that \usepackage{tikz} is also in the preamble. Likely obvious from my question but just in case ...