Your server sends the mail to Outlook only after one day. What did they answer when you asked them why?

More details are needed:
- what 'outlooks'?
- what account type (Exchange Server, pop3, imap)?
- what mail provider (like: gmail.com, tiscali.co.uk)
- do you have access to a webmail service to your e-mail account?
- if you use another email client (like Thunderbird) does that receive the mail immediately, or also with a one day delay?
- can you force an update by clicking something like 'refresh' or 'receive mail' or f5 in your 'outlooks'?

Kees