How do i keep from getting error messages from outlook about yahoo server?

i receive emails fine, but when i send them i keep getting an error message that says that the connection to the server was interrupted. i have followed the directions on yahoo with checking boxes and changing ports. still doesn't work. any suggestions?How do i keep from getting error messages from outlook about yahoo server?
this happens to me a lot.i don't know if i'm sending at the wrong time or servers down or what? sometimes it comes from yahoo!mail daemon,saying ,%26quot;sorry we tried%26quot; %26amp; it wouldnt go through.,,it's then i do not have the correct address.i tried to e-mail my neice 5 times before i got it to go through.i had her info wrong in my address book,it called her by the incorrect name.i didnt think that matters but apparantly it does.sometimes i'll send a note saying%26quot;testing,to see if this goes through,%26quot; just to see if it will go..keep trying %26amp; maybe re-check your name%26amp;address of your sender.good luck..