mail no longer working after upgrade to Ventura 13.4.1

Yesterday after upgrading to Ventura 13.4.1 I found I could no longer send or receive email. This applied to both my iCloud and gmail mail address. Trying to send via iCloud I get:

Mail was unable to connect to server “p39-smtp.mail.me.com” using SSL on the default ports. Verify that this server supports SSL and that your account settings are correct.

Whilst it may be a coincidence mail was working correctly before the upgrade to 13.4.1 but stopped working immediately after installing the upgrade.

Any help appreciated.