Looks like this error message in the desktop sync client:
<message>
<location filename="../src/libsync/propagatedownload.cpp" line="727"/>
<source>The downloaded file is empty despite the server announced it should have been %1.</source>
<translation>Le fichier téléchargé est vide bien que le serveur indique que sa taille devrait être de %1.</translation>
</message>