XCON: Event 13005 During POP3 Logon

When you attempt to connect to Exchange Server version 5.5 computer with a POP3 client, you may receive the following error message:

The credentials being passed from the client to the Exchange Server computer do not match the user's Windows NT account and/or mailbox.

1. Check the client configuration; please note that the steps for checking the configuration will vary depending on the type of client being used.
2. Change the account name to the format of NT_domain\NT_account\Exchange_alias.
3. Set the password to match the Windows NT password.
4. Save the changes, exit the client, and restart the client.
5. Connect to the Exchange Server POP3 service.

For an alternate resolution to this issue:

Change the alias name of the mailbox to the same as the NT account name. This will enable you to use one account name (instead of typing in the full path as described above).

If the connection still fails, follow the troubleshooting steps in the following article in the Microsoft Knowledge Base: NOTE: The format of NT_domain\NT_account\Exchange_alias should work when using Outlook 98 or Outlook Express clients. Results may vary when other clients are being used.