Claire reported that when she opened Agresseure, a copy of Correction opened. I checked the files on Endive and my backups, and determined that:

1. The files are different on my backups, so prior to January 4, the files were different.
2. The file dates on Endive show that both files were saved on January 4.

The most likely explanation is that Claire or France saved the correction.xml file over the top of the agresseure.xml file. I've solved the problem by copying my backup of agresseure.xml over the top of the file on Endive. My backup was from November 29, so any changes made to agresseure.xml after that date will have been lost, but I suspect there weren't any (unless you made some on January 4, in which case they were lost anyway when correction.xml was saved over the top, unfortunately).