Hi everyone,
I feel I may have something to offer this post.
Please Note: This may have already been suggested, however I'm far too busy to go through 3+ years worth of posts to see if it indeed has!
The issue:
Ok, so I have the same issue as a lot of you seem to have - and have done for over 12 months now: Emails in Mac 'Snail' Mail not reaching the sent folder (or the server) upon send, if set up as IMAP - recipient still gets the email - I no longer have a record of it (bloody ridiculous!).
This is what I feel i have to offer:
I ran some tests to see if I could establish a pattern to the missing emails, I FOUND ONE:
Basically when I send an email (so create the email as normal and hit send) and then straight away start to navigate around Mac Mail (for example go straight to the sent folder, or some other folder) 9 out of ten times the email goes missing. HOWEVER, if I send the email, and leave Mail alone for a minute or two (go read a book, start another job in another application, go make a cup of tea or something - just do something that doesn't involve Mac Mail) the email reaches my sent folder. Bizarre! Also, try leaving mail alone until after the 'whooosh' sound, this works too!
The Result:
By leaving Mac Mail alone after sending the email 10 out of 10 emails reached my sent folder. SORT IT OUT APPLE!
Obviously, if you've got a lot of tasks to complete in Mail, you're screwed, as this process will make those tasks take even longer - but at least you'll have a copy of the sent email waiting for you.
Woodinho out.