Q When overseas, I access .me mail using iCloud, via an unreliable wireless router which often drops connections. Sending mail, this sometimes does not complete properly, and messages are delivered to recipients but do not appear in the Sent mail on my Mac. Is Mail, the ISP, or iCloud at fault?
A First check your account preferences in Mail, ensuring that in the Mailbox Behaviours tab of the Accounts section all the items except the top one (Store draft messages on the server) are checked and the upper two popups are set to Never.
When in areas with dodgy Internet connections, work offline until ready to sync; then when you think the connection will stand it, go online just to collect and send messages. If a mailbox is behaving erratically, back up your mail folder from ~/Library/Mail, go online with a reliable connection, and rebuild that mailbox. The IMAP accounts used for .me addresses are more robust than ordinary POP/SMTP, but like all cloud systems rely on good server connections.
Updated from the original, which was first published in MacUser volume 28 issue 23, 2012.