The account I've been using for 20+ years is xxx@talk21.com Officially my account was renamed as xxx.t21@btinternet.com a few years ago but it's the same account which is a premium account. Following the advice from the Premium mail team I removed my account from the Windows 10 Mail app (New Outlook) and added it again. My messages have not all downloaded. Only 8 messages have so there is obviously a syncing issue. On the Mail app on my iPad, I removed the account and added it again. The messages have all downloaded. I can receive messages, but when I try to send a message I get the error message. Cannot Send Mail: The connection to the outgoing server "mail.btinternet.com" failed. Additional Outgoing Mail Servers can be configured for Mail accounts in Settings > Mail > Accounts.
