Bernt Guldbrandtsen <bernt.guldbrandtsen@mbg.au.dk> writes:

> Recently, generating previews under AUCTeX started to fail. Until some months ago,
> I had a working setup.  The OS is Windows 10 (updated). A minimal working
> example is shown below. Running LaTeX on _region_.tex works and the PDF
> file produced contains the expected content. However, running gs fails
> with no diagnostics.
>
> The machine has MiKTeX's mgs and "normal" gswin64 installed. At the
> Cygwin command prompt both can run the conversion successfully. MiKTeX
> (64 bit version) is updated and has mgs version 9.25. Ghostscript (64
> bit version) is updated and is version 9.27.
>
> In Emacs,
>
>    M-! mgs
>    
> and
>
>    M-! gswin64
>    
> find mgs and gswin64 respectively as expected.
>
> A command such as
>
>   mgs -dDELAYSAFER -sDEVICE=png16m -dPrinter -dNOPLATFONTS
>     -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -o 'pic-%d.png'
>     _region_.pdf
>
> produces the expected png output file.
>
> It looks like mgs fails to run at all despite that Emacs is able
> to find mgs.exe correctly.
>
> Any pointers?

Hi Bernt,

thanks for the report.  I tried your example and it works for me: