# Compiling a given latex file

I'm trying to compile BPI.tex here because, as you can see, the given compiled file has the lower end of each page cut off. The problem is: I get lots of "undefined control sequence" errors but if I cut the paragraph containing the error, delete aux and log files, quit TexShop and then recompile, I get the same error on the same line even if the line is then blank (since I cut it out).

What is going on here? Is TexShop broken? Why does editing the file not have any effect? And how can I compile this file?

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@Jubobs The file I'm trying to compile is really long. What should I do? Copy paste the beginning and the end of it? – Matt N. May 26 '13 at 10:20

The file is meant to be compiled with amstex rather than LaTeX. Just move the first line after the second one

\input amstex
\undefine\eth
\documentstyle{amsppt}
\NoBlackBoxes
<...>


and use "Plain TeX" as the typesetting engine from the drop down menu

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You are a lifesaver! It's like magic! Thank you so much! – Matt N. May 26 '13 at 10:22
@MattN. Ages ago I was using amstex myself. ;-) – egreg May 26 '13 at 10:25