A message landed in spam: what should I do?
“Junk” mail (also called “spam”) is the messages the server thinks are advertising or dangerous. It sometimes gets it wrong.
Step by step
In Mail, click the Indésirables (Junk) folder, in the folder column.
Open the message you were expecting.
Click Déplacer vers un dossier (Move to a folder) (above the message, on the right), then Boîte de réception (Inbox).