The "Problem with sync" occurs on sending e-mail from IMAP accounts. Exchange and Google mail accounts can send mail.
I have tried different settings for authentication like TLS, SSL, different ports. Mails stay in the Outbox, which keeps "Updating" forever.
In another thread this sync problem is being discussed as well. For me it means I cannot rely on the Jolla right now and have to keep my N9 at hand. I asked care@jolla.com for help yesterday evening.