Package hyperref provokes Runaway argument

[Roger Price]

On Mon, 7 Nov 2022, Roger Price wrote:
>
> My document source ML.tex is minimal:
>
>   \documentclass{article}
>   \usepackage{hyperref}
>   \begin{document}
>   Hello
>   \end{document}
>
> When I run pdflatex I get the error message
>
>   Runaway argument?
>   {\045keyword, error recove
>   ! File ended while scanning use of \@@BOOKMARK.
>   <inserted text>
>                   \par
>   l.3 \begin{document}

My error was to not remove the previous .out file before running pdflatex. Once 
I did this, the Runaway argument disappeared.

Roger