beamer over miktex 2.9 is not working with math environment

I have this problem where I can't built slide documents with beamer every time I include a math environment as simple as $\mu = A$. The log file posts this message at the end:

!pdfTeX error: miktex-pdftex.exe (file mathkerncmssi10): Font mathkerncmssi10 a
==> Fatal error occurred, no output PDF file produced!


I understand that the file (mathkerncmssi10) that is apparently missing is part of the package sansmathaccent, but the package is already there and updated.

This is driving me crazy, I would appreciate any help.

Sure, I tried this with several examples. I can post this one

\documentclass{beamer}
\usepackage[latin1]{inputenc}
\usetheme{Warsaw}
\title[Make a LaTeX presentation using Beamer]{Introduction  to Beamer\\How to make a presentation with LaTeX?}
\institute{Math-linux.com}
\date{Jule 13, 2007}
\begin{document}
\begin{frame}
\titlepage
\end{frame}
\begin{frame}{Introduction}
This is a short introduction to Beamer class.
$\mu=A$
\end{frame}
\end{document}


By the way, it turns out that I just tried this one in another PC and works fine.

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This looks like a defective installation. I'd be tempted to run the MiKTeX update wizard: do it both in 'admin' and 'normal user' modes to make sure you get everything. –  Joseph Wright Jul 21 '12 at 6:33
Your pdftex.map-file hasn't been updated. Normally this happens if you have a local pdftex.map (in your user profile) created e.g. by an on-the-fly installation. In such cases you must run updmap to update the map if you install a font. –  Ulrike Fischer Jul 21 '12 at 10:24
I don't understand why this topic has been closed. I had the same problem and @UlrikeFischer's solution has rescued me. –  Stéphane Laurent Sep 29 '13 at 9:35
Can someone with enough privileges vote to reopen? I had the same problem too, solved running C:\Pragram Files\MiKTeX\miktex\bin\updmap.exe, thanks @UlrikeFischer –  Oriol Dec 8 '13 at 21:40

Your pdftex.map-file hasn't been updated. Normally this happens if you have a local pdftex.map (in your user profile) created e.g. by an on-the-fly installation. In such cases you must run updmap to update the map if you install a font.
I have the problem cited by the OP, and unfortunately, your suggested fix does not resolve it. I did locate two files: xpdftex_ndl14.map and xpdftex_dl14 that could be culprits, I suppose. –  Steven B. Segletes Feb 7 '14 at 11:10