[chris]

Lili-
I found this on Eudora's website regarding the security settings. It might be worth a try:

In order to configure security in Eudora:

• Tap Menu.
• Tap Options.
• Tap Accounts.
• Tap the account you want to open and tap the Security tab. The dialog box is split between Incoming (POP) and Outgoing (SMTP) server information.
• Tap the Server Info button for either the incoming or outgoing server to receive details regarding server security (Secure Socket Layer, or SSL) on the last email check. If no security was detected, you will receive a pop up stating that no security was found.
• Tap OK to accept security settings.

Incoming (POP3)

• Tap Save Password for the incoming server if you want to save your password.
  NOTE: If you save your incoming server password, Eudora will prompt for your password the first time you check your mail. If you saved your password and want Eudora to forget it, uncheck the Save Password field.
  
• Tap the Authentication drop-down menu for a list of authentication types. Best Available is chosen by default, but you can change it to one required by your server. Best Available allows Eudora to automatically select the most secure authentication type offered by the server. The preferred POP authentication method is CRAM-MD5. If CRAM-MD5 is not available, Eudora automatically uses PLAIN. Click here for more info on CRAM-MD5.

Outgoing (SMTP)

• Tap the Authentication drop-down menu for a list of authentication types. Eudora can log in to an SMTP server when sending mail, just like it does for receiving mail. However, not all SMTP servers require or allow such authentication. By selecting Best Available, you allow Eudora to automatically select the most secure authentication type offered by the server. The preferred SMTP authentication method is CRAM-MD5. If CRAM-MD5 is not available, Eudora automatically uses PLAIN.
• If the SMTP server requests a password from the Eudora application, tapping one of the following options from the outgoing server's secondary authentication menu tells Eudora how to respond.
  
  1. Don't Authenticate - Ignore the server's request for a password and send messages anyway. Some servers require password authentication, so the messages will not be sent.
     
  2. Same As Incoming - Use the incoming username and password to authenticate. This is the default setting.
     
  3. Password Prompt - Prompt for username and password with a dialog box. If you select this option and tap the Save Password checkbox in the dialog box, Password Saved replaces Password Prompt as one of the options in the menu.
     

Unfortunately, Eudora discontinued upgrades/support on their PDA Internet Suite. If you continue to have problems, you might want to try another application such as SnapperMail. I've been using the standard version for years and swear by it. You can always trial it to see if it meets your needs.

Good luck.
-Chris