[texworks] problem with \magstep1

[Akira Kakuto]

> Thank you for your comments.
> What can I do to correct the problem?

Try

%Sample file
%  
%
\magnification\magstep3
\pdfpagewidth=210 true mm
\pdfpageheight=297 true mm
\pdfhorigin=1 true in
\pdfvorigin=1 true in
... ...
\bye

Best,
Akira