# Error: Entry Status for cite key when using achemso

I am adapting the demo file from the achemso package for my manuscript. When removing citations (in this case by commenting the section on References) I get a number of errors which look like this:

! Package mciteplus Error: Entry Status for cite key Mena2000' under
tracking ID main' is undefined, treating it as a head entry. See the
mciteplus package documentation for explanation. Type H <return> for
immediate help.


I use Texmaker 5.0.2, MiKTeX 2.9.6703, achemso 3.11a, and mciteplus 1.2 on Windows 7 64 bit.

So far I found the following suggestions, none of which seem to work:

• Move bibliography to the end. If I am not mistaking this is already the case (i.e. the end of the tex file looks like this:

\bibliography{achemso-demo}
\end{document}

• Alter achemso.sty and achemso.cls. I have added \RequirePackage{natmove} on line 320 and line 1407 respectively, just before \RequirePackage{mciteplus}.

• \usepackage[sort&compress,numbers,super]{natbib}
\usepackage{achemso}


However I don't think the demo is using the achemso package that way.

This error only occurs when I change citations after building. The initial build completes succesfully.

Any help is greatly appreciated.

EDIT: Following Troy's suggestion, here is a (semi-)MWE adapted from the achemso demo. The reason for the relative lengthy example is that if I remove any citation, it fails to build. Therefore I have only commented the last paragraph to generate the following error:

! Package mciteplus Error: Entry Status for cite key Note-1' under tracking ID
main' is undefined, treating it as a head entry.
See the mciteplus package documentation for explanation.
Type H <return> for immediate help.
...
l.128 \bibitem[Not()]{Note-1}
I don't have a record of the head/tail status of this citation. Possible reason
s include the use of a cite command that is not mciteplus aware, the use of \n
ocite{*}', or a problem with the tracking ID and/or aux file handles. \mciteEr
rorOnUnknownfalse' can be used to disable this error message.

! Package mciteplus Error: Entry Status for cite key Note-2' under tracking ID
main' is undefined, treating it as a head entry.
See the mciteplus package documentation for explanation.
Type H <return> for immediate help.
...
l.135 \bibitem[Not()]{Note-2}
I don't have a record of the head/tail status of this citation. Possible reason
s include the use of a cite command that is not mciteplus aware, the use of \n
ocite{*}', or a problem with the tracking ID and/or aux file handles. \mciteEr
rorOnUnknownfalse' can be used to disable this error message.


Here's the MWE:

\documentclass[journal=jacsat,manuscript=article]{achemso}

\usepackage{chemformula} % Formula subscripts using \ch{}
\usepackage[T1]{fontenc} % Use modern font encodings

\newcommand*\mycommand[1]{\texttt{\emph{#1}}}

\title[An \textsf{achemso} demo]
{A demonstration of the \textsf{achemso} \LaTeX\
class\footnote{A footnote for the title}}

\begin{document}

The class makes various changes to the way that references are
handled.  The class loads \textsf{natbib}, and also the
appropriate bibliography style.  References can be made using
the normal method; the citation should be placed before any
punctuation, as the class will move it if using a superscript
citation style
\cite{Mena2000,Abernethy2003,Friedman-Hill2003,EuropeanCommission2008}.
The use of \textsf{natbib} allows the use of the various citation
commands of that package: \citeauthor{Abernethy2003} have shown
something, in \citeyear{Cotton1999}, or as given by
Ref.~\citenum{Mena2000}.  Long lists of authors will be
automatically truncated in most article formats, but not in
supplementary information or reviews \cite{Pople2003}. If you
encounter problems with the citation macros, please check that
your copy of \textsf{natbib} is up to date. The demonstration
database file \texttt{achemso-demo.bib} shows how to complete
entries correctly. Notice that \latin{et al.}'' is auto-formatted
using the \texttt{\textbackslash latin} command.

Multiple citations to be combined into a list can be given as
a single citation.  This uses the \textsf{mciteplus} package
\cite{Johnson1972,*Arduengo1992,*Eisenstein2005,*Arduengo1994}.
Citations other than the first of the list should be indicated
with a star. If the \textsf{mciteplus} package is not installed,
the standard bibliography tools will still work but starred
references will be ignored. Individual references can be referred
to using \texttt{\textbackslash mciteSubRef}:
ref.~\mciteSubRef{Eisenstein2005}''.

%The class also handles notes to be added to the bibliography.  These
%should be given in place in the document \bibnote{This is a note.
%The text will be moved the the references section.  The title of the
%section will change to Notes and References''.}.  As with
%citations, the text should be placed before punctuation.  A note is
%also generated if a citation has an optional note.  This assumes that
%the whole work has already been cited: odd numbering will result if
%this is not the case \cite[p.~1]{Cotton1999}.

\bibliography{achemso-demo}

\end{document}

• Welcome to TeX.SE! Please help us help you and add a minimal working example (MWE) that illustrates your problem. Reproducing the problem and finding out what the issue is will be much easier when we see compilable code, starting with \documentclass{...} and ending with \end{document}.
– Troy
Jun 19, 2018 at 13:33
• I had a similar problem and moving the bibliography to the end of the document worked for me. Since it didn't work for you, I think there may be many different causes to this error. It would be nice if someone could give a thorough answer to this question. Aug 14, 2018 at 20:37

Here is a fix which I have found to solve the above issue. Just use the following command after loading the mciteplus package in the preamble:

\mciteErrorOnUnknownfalse

This helped me to get rid of the error easily after loading it in the preamble. Hope it helps to fix your error too.

• A while after I first saw this question, this was the answer that solved the issue. Could you add a reference to your solution? Feb 7, 2019 at 18:08

I don't know if this can work in any operating system but in ubuntu i open terminal and type:

sudo apt-cache search mciteplus


(to look packages to need to be installed) the result was:

texlive-latex-extra


so i type:

sudo apt install texlive-latex-extra


and that solve the problem for me, i hope it helps.

• Welcome to TeX.SE! Oct 13, 2021 at 15:32

same problem.
I do not like to override the security in this type of things.
\mciteErrorOnUnknownfalse

• If it's an issue with the .aux, wouldn't deleting it be sufficient to correct for the problem?