Still same problem.
As I said if I disconnect from my provider router and connect to my Mobile phone WIFI router I am even not able to connect the imap of my 1st account @ovh.net, the one which worked fine on my FREEBOX router.
In addition, the strange thing is the connection works for a while from time to time ??
It seems there is a timing problem somewhere.
With COURRIER all my mailboxes works fine in any WIFI configurations …