Sorry for these multiple replies.
Besides Emacs, I also have Cygwin and Msys32 installed in my Windows system.
And at the beginning of my Emacs init file I have this:
(setenv "PATH" (concat
"C:\\msys32\\mingw32\\bin;C:\\cygwin\\bin;C:\\cygwin\\lib;" (getenv "PATH")))
(setq exec-path (append '("C:/cygwin/bin" "C:/cygwin/lib"
I wonder whether AUCTeX in my case is using some command from cygwin to update
TEXINPUTS, and that takes care of the ";".
Do you also have cygwin on your system?
But I think that by now David has already guessed where the problem is, so I'll
see what he says.
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