UPDATE: Deleting the Cache using

rm -rf `biber --cache`

solved my problem.

I'm a new user of LaTeX and use it the first time to write a thesis. Up until now I had everything running fine and was polishing my text as my citations didn't process anymore. I use Biblatex and Biber and export my literature automatically from Zotero.

This is a example:


\geometry{left=3cm, right=4cm, top=3cm, bottom=3cm}

\usepackage[backend=biber, style=apa]{biblatex}


This is some Text.

And a really important citation \parencite{neugebauer2020}.

The \textcite{rkimeasles2020} has some totally important findings.


With these in the .bib file:

  title = {Beurteilung des neuen Masernschutzgesetzes in Deutschland: Ergebnisse einer deutschlandweiten Befragung},
  shorttitle = {Beurteilung des neuen Masernschutzgesetzes in Deutschland},
  author = {Neugebauer, Michael and Ebert, Matthias and Vogelmann, Roger},
  date = {2020-11-25},
  journaltitle = {Zeitschrift für Evidenz, Fortbildung und Qualität im Gesundheitswesen},
  volume = {158-159},
  pages = {74--80},
  issn = {18659217},
  doi = {10.1016/j.zefq.2020.10.009},
  url = {https://zefq-journal.com/article/S1865-9217(20)30171-9/abstract},
  urldate = {2021-01-27}

  title = {{{RKI}}-Ratgeber - {{Masern}}},
  editor = {{Robert Koch-Institut}},
  date = {2020},
  url = {https://www.rki.de/DE/Content/Infekt/EpidBull/Merkblaetter/Ratgeber_Masern.html},
  urldate = {2021-01-04},
  file = {/Users/dennis/Zotero/storage/AJTINZFI/Ratgeber_Masern.html}

Running this using Texmaker (Xelatex -> biber -> Xelatex outputs this:

Process started

Unicode::UCD: failed to find unicore/version in /var/folders/sn/mrxx700x6wjbb_wbvjt1_x480000gn/T/par-64656e6e6973/cache-2f8a664c3c933a44d096bcc8d018a5e92bced897/inc/lib /var/folders/sn mrxx700x6wjbb_wbvjt1_x480000gn/T/par-64656e6e6973/cache-2f8a664c3c933a44d096bcc8d018a5e92bced897/inc CODE(0x7f871ef8cad8) CODE(0x7f871ef8d0c0) at /var/folders/sn mrxx700x6wjbb_wbvjt1_x480000gn/T/par-64656e6e6973/cache-2f8a664c3c933a44d096bcc8d018a5e92bced897/inc/lib/Biber/Internals.pm line 1238.

INFO - This is Biber 2.14 INFO - Logfile is 'Testtex.blg' INFO - Reading 'Testtex.bcf' INFO - Found 2 citekeys in bib section 0 INFO - Processing section 0 INFO - Globbing data source 'Literatur.bib' INFO - Globbed data source 'Literatur.bib' to Literatur.bib INFO - Looking for bibtex format file 'Literatur.bib' for section 0 INFO - LaTeX decoding ... INFO - Found BibTeX data source 'Literatur.bib' WARN - Entry 'neugebauer2020' (Literatur.bib): Invalid format '2020-11-25' of date field 'date' - ignoring WARN - Entry 'neugebauer2020' (Literatur.bib): Invalid format '2021-01-27' of date field 'urldate' - ignoring WARN - Entry 'rkimeasles2020' (Literatur.bib): Invalid format '2020' of date field 'date' - ignoring WARN - Entry 'rkimeasles2020' (Literatur.bib): Invalid format '2021-01-04' of date field 'urldate' - ignoring

Process exited with error(s)

Running with Latexmk or Biber directly gives me the same Warnings about the invalid date format.

Biber warning: [217] Utils.pm:304> WARN - Entry 'neugebauer2020' (Literatur.bib): Invalid format '2020-11-25' of date field 'date' - ignoring

I'm at a loss here. From my point of view the date format is correct. I also tried deleting the Biber Cache. No Change.

Any ideas?

  • 1
    Delete the Biber cache as described in tex.stackexchange.com/q/140814/35864. Follow the exact steps there. Make sure you don't delete the wrong Biber cache (you might have several from older Biber versions.) See also tex.stackexchange.com/q/541486/35864.
    – moewe
    Feb 20 '21 at 15:47
  • Your Biber cache is definitely corrupted. The Unicode::UCD: failed to find unicore/version error should definitely not be there. If deleting the cache and re-running Biber does not fix the cache, then maybe you have an antivirus or other security software blocking proper cache extraction. Or maybe you have a very eager cleaning software that tries to delete 'unused' files in the temp directory.
    – moewe
    Feb 20 '21 at 15:54
  • Thank you! I retried deleting the Biber Cache. Previously I tried rm -rf "biber --cache". putting biber --cache instead solved the problem for me.
    – Ntgllr
    Feb 20 '21 at 16:00
  • It's quite possible that rm -rf "biber --cache" or some such trick does not work if biber --cache also throws a warning or an error. In that case it might help to run just biber --cache, see where you are pointed and to then remove that directory manually.
    – moewe
    Feb 20 '21 at 16:03

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