# Error when using greek symbol in subscript in beamer presentation [duplicate]

I am working on a beamer presentation which will include many mathematical symbols. I use MiKTeX 2.9 and the TeXstudio IDE.

I have run into a problem when I attempt to use certain mathematical symbols. Here is a MWE:

\documentclass{beamer}

% Document
\begin{document}

\begin{frame}
\begin{itemize}
\item This is normal text
\item This item has a greek symbol: $\alpha$
\item This item uses it as a subscript $C_\alpha$
\end{itemize}
\end{frame}

\end{document}


I use \alpha twice, once normally and once in a subscript. However, this only compiles without the third item. If that is included, this produces the error:

!pdfTeX error: pdflatex.exe (file mathkerncmssi10): Font mathkerncmssi10 at 657
==> Fatal error occurred, no output PDF file produced!


I have made a web search for similar error texts and found nothing. I have no idea how to further proceed, and would appreciate any hints at what is actually going wrong.

### Update 1

It seems this is not related to the \alpha symbol at all, but instead just caused by any letters I try to typeset in mathmode. Including

\item $a$


already causes this error and fails to produce any output document.

• i can't reproduce the problem. instead of the error you receive, my attempt results in this warning: "LaTeX Font Warning: Font shape 'OT1/cmss/m/n' in size <4> not available (Font) size <5> substituted on input line 12.". (i'm still running with tex live 2012, and it's possible that some font names have changed.) i would interpret the error you got to mean that you don't have type 1 (outline) fonts, only bitmaps. – barbara beeton Jun 15 '15 at 16:45
• If I compile the code you wrote, I don't get any error and the pdf produced looks perfect. You should provide a MWE, i.e. a code that reproduces that error. Surely you're loading some font that causes the problem. – MyUserIsThis Jun 15 '15 at 16:47
• @MyUserIsThis This exact code results in the error I described in my system. – MaxAxeHax Jun 15 '15 at 16:51
• @barbarabeeton Thanks, would you have any idea on what I could try to do to fix it? I have searched the MiKTeX repository for the "mathkerncmssi" and "mathkerncmssi10" fonts without success. In my real use case I also don't fiddle with fonts nor themes for beamer, and just go with the default. – MaxAxeHax Jun 15 '15 at 16:53
• The error message indicates that your system is perhaps not up-to-date (run the update manager (both, admin and user version), and that you need to run on the command line updmap to update your map files. Changing the font like in the accepted answers avoids the error but does not solve the underlying problem. – Ulrike Fischer Jun 16 '15 at 7:12

If the answer of @Alder Miguel is not sufficient, try also adding

\usepackage[T1]{fontenc}
\usepackage{lmodern}


Try adding the \usepackage[utf8]{inputenc} to show LaTeX how to recognize some characters. I have compiled this code:

\documentclass{beamer}
\usepackage[utf8]{inputenc}

\begin{document}

\begin{frame}
\begin{itemize}
\item This is normal text
\item This item has a greek symbol: $\alpha$
\item This item uses it as a subscript $C_\alpha$
\end{itemize}
\end{frame}

\end{document}


Using this code I´m getting this: