Error Message: Cannot send email because the message is "too big".

Help! Once I sent a large email. I received an error message for that, and for every small email I sent after that: “An error occurred. Cannot send message … due to the following reason: Message size exceeds maximum permitted.” ~ I use version 7.1.31849.0 

This is typically not an eM Client issue, but a restriction of your email provider.  The other, smaller messages may be stuck in your outbox because of that large one.  Try deleting the large message from your outbox (the outbox is a local folder, so make sure they are visible by going to menu/tools/settings/general and in the general section check “Show local folders”).

After you delete the large message, see if the other go through.