cannot send in outlook - new Vista user

I get this error message " 'mail.mchsi.com', Protocol: SMTP, Port: 25,
Secure(SSL): No, Error Number: 0x800CCC19." I downloaded 32 bit update last
month which worked, now I am unable again to send and when I tried the same
fix again, it said my system didn't support it. I'm not too literate with
this... and am frustrated!