That depends on your version of OL
In 2003, ToolsOptionsMail Setup Tab......tick the obvious

"Jimmy" wrote in message
news
I'm sure the answer is staring me in the face but I can't find it. I had
Outlook setup to send and receive mail when the program opens. I just
reinstalled onto a new computer and I can not for the life of me, find
where
that option was. I found the option to set a time interval to check and an
option to send/receive on exit but not on open? Where is it???