outlook not sending emails

My OUtlook 10 out of the blue stopped sedning emails.  I was receiving emails.  The error 0x80042112 was displayed with message to conatct the ISP which I did - btinternet.  Totally useless- got me to delete my account (emails did not disappear) and add new to re-create my account.  Now I still can't send emails, but the ones I receive - I see the little box appear when there's a new one - disappear somewhere!  They are not in the Inbox and I've looked in all folders - don't know where they are.  Please help!!!  I am not very technical so please answers in the form of Outlook for Dummies would be much appreciated!!