Please note: These pages are no longer updated and maintained.
We have moved all the information in these pages into the AoPSWiki, which
are updated and improved by the AoPS Community. Click
here to go to the corresponding page in the AoPSWiki.
When you use TeXnicCenter, a separate window contains output from LaTeX
concerning various compiling information, including errors. Much of this
text can be ignored. However, if you see a 
symbol, you have a serious problem.
If you have a whole string
of these error messages, scroll back until you hit the first one. Often one
error will cause many others, so you should fix them starting with your first
problem. Also, the output from the compiler will give you a line number to help
you find the error in your code. In TeXnicCenter, the line number you are on
is given at the bottom of the TeXnicCenter window on the right.
Here are some common error messages,
as well as other possible problems, and a little information about what the
problem usually is. Most of these error messages will appear right after the
. Occasionally, they will
appear 1-2 lines before it. A few of these are just warnings - they generate
yellow triangles in TeXnicCenter when compiling.
- Extra
alignment tab has been changed to \cr.
- LaTeX
Error: \begin{something}
on input line line number
ended by \end{document}
- LaTeX
Warning: Reference ... undefined on ....
- LaTeX
Warning: There were undefined references.
- Missing
$ inserted
- Paragraph
ended before \end was complete.
- Runaway
argument?
- Undefined
control sequence.
Here are some problems that might occur that don't have error messages in
the compiler:
- Forget
the error messages, when I try to compile, it starts, but then just hangs.
Nothing happens, and I can't do anything. Then when I try to save the file,
it won't let me save it with the same name.
- I'm
trying to use fancyhdr to make headers and footers, but they don't align with
the rest of my page. The rest of the page extends beyond the header line to
the right or left.
- I'm
using referencing, but the page numbers or equation numbers aren't coming
out right.
If you have an error that's not on
this list, post
it on the message board and someone may be able to help.
Possible
solutions to the errors above
- Extra
alignment tab has been changed to \cr.
You have too many &s in
a row of a table or array or eqnarray.
- LaTeX
Error: \begin{something}
on input line line number
ended by \end{document}
You've left out the \end{whatever}.
Perhaps you're building a table or an eqnarray that has a bunch of lines and
you've forgotten the \end statement.
- LaTeX
Warning: Reference ... undefined on ...
You have references in
your document. You need to compile again so LaTeX
will be able to get the references right.
- LaTeX
Warning: There were undefined references.
You have
references in your document.
You need to compile again so LaTeX
will be able to get the references right.
- Missing
$ inserted
You left out a $ or \[ or \] or $$ somewhere. when you were writing text that
needs to be in math mode.
- Paragraph
ended before \end was complete.
You are probably missing an } at the end of an \end{something}
statement.
- Runaway
argument?
A runaway
argument occurs when you leave off a }.
- Undefined
control sequence.
You've tried to call a command that doesn't exist. Usually this is the result
of a typo. Go to the line number mentioned in the error and look at all your
commands. You'll probably find something like \rfac
where you wanted \frac.
- Forget
the error messages, when I try to compile, it starts, but then just hangs.
Nothing happens, and I can't do anything. Then when I try to save the file,
it won't let me save it with the same name.
You probably have tried to use a package that you haven't installed. For example,
if you try \usepackage{fancyhdr}
but haven't installed the package, then
you'll hang TeXnicCenter so badly that you should just restart your computer
(or, if you know how, kill the latex process you've started).
- I'm
trying to use fancyhdr to make headers and footers, but they don't align with
the rest of my page. The rest of the page extends beyond the header line to
the right or left.
You probably have called \textwidth
(or some other command dealing with page dimensions) after the \pagestyle
command in your preamble. The \pagestyle
and header and footer commands should come after all the page dimensions are
set in the header.
- I'm
using referencing, but the page numbers or equation numbers aren't coming
out right.
You have references
in your document. You need to compile again so LaTeX
will be able to get the references right.
