Could not resolve mount point /mnt/dir
did you create /mnt/dir first? that directory must exist (or feel free to use whatever other mount point you want).
also, you're trying to access //FAMILLE/F - which i suppose is your F: drive in windows. as far as i know, you can't share a drive that way, you have to share a specific folder. in other words, in windows i have the following directory that i want to share from my windows pc named maverick:
the command to mount this on a remote linux computer would be:
smbmount //maverick/Pics /mnt/pics