550 error when sending

This normally means that you do not have your outbound authentication turned on in your email client.

You will need to enable this for all of your email accounts that you are using to send out mail using your mail server.

*Outlook and Outlook Express*
To configure authenticated SMTP in Outlook Express:
1. From the Tools menu, select  “Accounts… ”
2. Highlight your Mail account (it may be called mail.domain.com).
3. Click the “Properties” button on the right side.
4. Choose the “Servers” tab.
5. Check the box next to “My server requires authentication.”
6. Click the “Apply” button.
7. Click the “OK” button.

*Netscape Messenger*
To configure authenticated SMTP in Netscape Messenger:
1. From the Edit menu, select “Preferences…”
2. Click the plus (+) icon next to “Mail & Newsgroups”
3. Choose “Mail Servers.”
4. In the “Outgoing mail server user name” field enter Username
5. Click the OK button.

*Eudora*
To configure authenticated SMTP in Eudora:
1. From the Tools menu, Select “Options…”
2. Click on the the  “Sending Mail ” icon.
3. Check the box next to “Allow authentication.”
4. Click the OK button.

*Microsoft Entourage*
To configure authenticated SMTP in Entourage:
1. From the Tools menu, select  “Accounts.”
2. Double-click your Mail account (it may be called mail.domain.com).
3. Click on the  “Click here for advanced sending options ” button.
4. Check the box next to “SMTP server requires authentication.”
5. Select the radio button next to “Use same settings as incoming mail server.”
6. Click the OK button

*Mozilla’s Thunderbird*
To configure authenticated SMTP in Thunderbird:
1. From the “Tools” menu, click “Account Settings”
2. Select  “Outgoing Server (SMTP) from the menu to the left.
3. CHECK the box for  “Use name and password “, input your full email address – i.e. user@domainname.com
4. Under  “Secure connection “, click “No”.
5. Click  “OK “.
*You will be prompted for a password when you first send a message. You will be given an option to save this password for future emails.