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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:



Just a test


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:

File: standard.bbx 2016/05/14 v3.4 biblatex bibliography style (PK/JW/AB)
! Illegal parameter number in definition of \blx@defformat@d.
<to be read again> 
l.368 ...ts{\usebibmacro{name:apa:last-first}{#1}{#3
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, Thorsten Jun 4 '17 at 13:38

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  • Welcome to TeX.SX! You can have a look at our starter guide to familiarize yourself further with our format. – Martin Schröder Oct 28 '16 at 5:12
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    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
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    Once you've got the packages sorted out, you also need to set the language mapping. See problems using apa6e with biblatex-apa. Also, a lot of these sorts of problems on Linux can be solved by not using the packaged versions of TeX Live but using a proper TeX Live install. See How to install "vanilla" TeXLive on Debian or Ubuntu? – Alan Munn Oct 28 '16 at 14:05
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    Thanks for the information. I had to do some searching, but I found a copy of biblatex-apa version 6.9, and now things are actually working correctly. – Reteo Oct 28 '16 at 22:16