# Errors for using “style=apa” with biblatex [duplicate]

I am currently using biblatex version 3.4, Biber version 2.5, and biblatex-apa version 6.6, on a 2015 TeXLive distribution in Gentoo (x86-64).

I'm not sure what's happening, but just including the biblatex package (nothing else) causes a large stream of ! Illegal parameter number in definition of \blx@defformat@d errors.

For an example, let's take the following basic code:

\documentclass[12pt,letterpaper]{article}
\usepackage[american]{babel}
\usepackage[style=apa,backend=biber]{biblatex}

\begin{document}

Just a test

\end{document}


There's absolutely nothing else with the document, no special commands or altered settings, nothing other than just the basic lines, and the addition of biblatex. No .bib files (yet), no citations, and no bibliography list has been added.

As long as style=apa is there, it will spit out a long list of errors, such as:

(/usr/share/texmf-site/tex/latex/biblatex/bbx/standard.bbx
File: standard.bbx 2016/05/14 v3.4 biblatex bibliography style (PK/JW/AB)
\c@bbx:relatedcount=\count219
\c@bbx:relatedtotal=\count220
)
! Illegal parameter number in definition of \blx@defformat@d.
3
l.368 ...ts{\usebibmacro{name:apa:last-first}{#1}{#3
}{#4}{#5}{#7}?}}
You meant to type ## instead of #, right?
Or maybe a } was forgotten somewhere earlier, and things
are all screwed up? I'm going to assume that you meant ##.


I can't use any other style, because the assignment I'm producing requires citations in APA format. Am I doing something wrong? Most of the searching I've done seem to result in questions relating to special circumstances, but as you can see, this is a vanilla document that just happens to have biblatex added to the usepackage list.

## marked as duplicate by TeXnician, Moriambar, CarLaTeX, Schweinebacke, ThorstenJun 4 '17 at 13:38

• Do your versions match? There was a change in some internals between biblatex v3.3 and v3.4 and the styles all had to be updated. – Joseph Wright Oct 28 '16 at 6:01
• Your versions of biblatex and biblatex-apa don't match. Try to update the packages. – moewe Oct 28 '16 at 6:08