I've sent an email from my iCloud account using Mail with an attachment (a 25K word document) and it didn't get delivered. It's in the Sent folder but it didn't reach the addressee (and I cc'd my Gmail account as well - also no joy). I tried to send it with Gmail cc'ing iCloud account - still no joy. I removed and re-added the iCloud account to Mail, restarted Mail, restarted the whole MacBook. Nothing. I tried to send it from icloud.com - nothing. I checked that I have 'Always send Windows-friendly attachments' ticked on, but still nothing. Emails without attachments are going through fine. Emails with other attachments are sending ok. I'm completely lost here... Any advice would be greatly appreciated...