Also check your trash folder. For years I had a problem with Yahoo automatically trashing emails with large files attached. It was one reason I decided to open a gmail account.
Yeh, do I tend to forget the spam folder, but incoming AWOL’s don’t seem to be going in there. Can’t exclude the possibility that outgoing AWOL’s are going into recipients spam folder though.
Reliability of yahoo hasn’t been that great,(search, one of the best features, was non-functional for months) and they keep revamping the interface (for no reason, in my view) rather than concentrating on making it work.
Inertia keeps me there, plus I prefer the original/“classic” interface to the competition, though that’s probably largely inertia as well.
Now that we’ve gotten that out of the way, I have noticed missing mails at times from them in the past too. My uncle still insists I must have blown him off a few years back. I still keep it from inertia though. I don’t use it for anything too important.