My Internet provider blocks port 25, how can I send e-mails?

For Outlook Express and Windows Mail:

Select menu Tools/Accounts and select your e-mail account. Press Properties button and select "Advanced" tab.

In Outgoing mail (SMTP) box type 26 and press "Apply", "OK" and "Close" buttons.

For Outlook 2003/2007

Select menu Tools/Account Settings. Select your POP3/IMAP account and select "Change" button

Press "More Settings..." button. Select "Advanced" tab

In Outgoing mail (SMTP) box type 26 and press "OK", "Next", "Finish" and "Close" buttons.