Automatic connection MATE desktop

I installed Linux Mint MATE 18.1.

The automatic connection to MATE is strange.
On one of my computer, if I activate the automatic connection, AND the connexion after 10 seconds (I would like to have less but it’s impossible), it works but I need to wait 10 seconds before the automatic connection. If I deactivate the connection after 10 seconds, the automatic connection doesn’t work anymore, I must connect manually !

On another computer, the automatic connection works when I activate the 10 seconds OR when I deactivate it (but I don't know if I really win 10 seconds, it seems as long as when I activate the 10 seconds).