# I'm trying to redefine the plain pagestyle as empty

I tried to use this command, but doesn't work.

\makeatletter
\let\ps@plain\ps@empty
\makeatother


I put it in the beginning, in the middle and just before the \begin{document}.

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Welcome to TeX.SE. It is always best to compose a fully compilable MWE that illustrates the problem including the \documentclass and the appropriate packages so that those trying to help don't have to recreate it. – Peter Grill Jul 29 '12 at 1:17
If you set the pagestyle to plain \pagestyle{plain} you should then get the desired result. – Peter Grill Jul 29 '12 at 1:18

You could use

\usepackage{nopageno}

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Page styles are merely a collection of macros which change the style of the page. Using

\makeatletter
\let\ps@plain\ps@empty
\makeatother


merely equates the two page styles in terms of what they do, but technically does not issue any page style. That is, you have to specify the page styles to be plain before they're actually changed. Therefore, also adding

\AtBeginDocument{\pagestyle{plain}}


(anywhere in your preamble) should make all your pages be styled as plain (which is empty).

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