[Tex/LaTex] Problem: Package atveryend Info: Empty hook `AtVeryVeryEnd’

bibliographiespackages

I am currently writing a paper and so far I had no problems whatsoever.
But all of a sudden the following happened and I can not see the reason for this major hick up. Can anyone help me?

The paper is written on Overleaf, the bib is imported via Mendeley.

------------------------------------------------------------------------------
 Bibliography
------------------------------------------------------------------------------

LaTeX Warning: Empty bibliography on input line 314.

Package atveryend Info: Empty hook `BeforeClearDocument' on input line 316.
Package atveryend Info: Empty hook `AfterLastShipout' on input line 316.
(./main.aux)
Package atveryend Info: Executing hook `AtVeryEndDocument' on input line 316.
Package atveryend Info: Executing hook `AtEndAfterFileList' on input line 316.
Package rerunfilecheck Info: File `main.out' has not changed.
(rerunfilecheck)             Checksum: 07A306AA181F0DDBE4806F9722871308;6068.


LaTeX Warning: There were undefined references.


Package biblatex Warning: Please (re)run Biber on the file:
(biblatex)                main
(biblatex)                and rerun LaTeX afterwards.

Package logreq Info: Writing requests to 'main.run.xml'.
\openout1 = `main.run.xml'.

Package atveryend Info: Empty hook `AtVeryVeryEnd' on input line 316.
 ) 
Here is how much of TeX's memory you used:
 25315 strings out of 493104
 413898 string characters out of 6136932
 818612 words of memory out of 5000000
 28313 multiletter control sequences out of 15000+600000
 18672 words of font info for 68 fonts, out of 8000000 for 9000
 1141 hyphenation exceptions out of 8191
 49i,12n,45p,10380b,1067s stack positions out of 5000i,500n,10000p,200000b,80000s
</usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmbx10.pfb></us
r/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmbx12.pfb></usr/shar
e/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmbx9.pfb></usr/share/texli
ve/texmf-dist/fonts/type1/public/amsfonts/cm/cmbxti10.pfb></usr/share/texlive/t
exmf-dist/fonts/type1/public/amsfonts/cm/cmcsc10.pfb></usr/share/texlive/texmf-
dist/fonts/type1/public/amsfonts/cm/cmr10.pfb></usr/share/texlive/texmf-dist/fo
nts/type1/public/amsfonts/cm/cmr12.pfb></usr/share/texlive/texmf-dist/fonts/typ
e1/public/amsfonts/cm/cmr6.pfb></usr/share/texlive/texmf-dist/fonts/type1/publi
c/amsfonts/cm/cmr8.pfb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfon
ts/cm/cmr9.pfb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cm
sl12.pfb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy10.p
fb></usr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmti10.pfb></u
sr/share/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmti12.pfb></usr/sha
re/texlive/texmf-dist/fonts/type1/public/amsfonts/cm/cmti9.pfb></usr/share/texl
ive/texmf-dist/fonts/type1/public/amsfonts/symbols/msam7.pfb>
Output written on main.pdf (46 pages, 4305376 bytes).
PDF statistics:
 894 PDF objects out of 1000 (max. 8388607)
 734 compressed objects within 8 object streams
 112 named destinations out of 1000 (max. 500000)
 323 words of extra memory for PDF output out of 10000 (max. 10000000)

Best Answer

Package atveryend

Message

Package atveryend Info: Empty hook `AtVeryVeryEnd'

is not a problem, it is just a message, neither warning nor error. It's more like a debug information, when the hook AtVeryVeryEnd is seen. If the hook is empty, then the message above is shown, if the hook is not empty, you will see:

Package atveryend Info: Executing hook `AtVeryVeryEnd'

Rationale: The package atveryend redefines \end{document}. This is per se risky, thus the package supports lots of packages and classes. But it may miss a package or class, which also redefines code about `\end{document}.

If this happens, a warning, that the hook is not seen is more useful, but if the redefinition fails, then the code of atveryend is not executed and therefore it cannot emit warnings.

The LaTeX message system does not have a "debug" category, only "error", "warning" and "info". Therefore these debug messages are using the lowest category "info".

Biber rerun warning

The only issue, that the .log file shows, is the rerun warning of package biblatex:

Package biblatex Warning: Please (re)run Biber on the file:
(biblatex)                main
(biblatex)                and rerun LaTeX afterwards.

Just do as the message say, run biber and pdflatex again. Usually this pdflatex run will again show a rerun warning, thus usually the following is needed:

biber main
pdflatex main
pdflatex main