SMTP set-up in GMail doesn't work in France

I am travelling in France and emClient won’t send my Gmail messages on my laptop - just puts them in Outbox. I have looked at Account Settings but the Diagnose option does not work - neither the IMAP or SMTP options show on this page so pressing Diagnose does nothing.

My current SMTP settings (which work fine in UK) are:

Host -

Port - 25

Security policy - Force Usage of SSL/TLS

Can you suggest settings that will work? Why does Diagnose not work?