I set up two accounts on Outlook Express Windows XP. Two different email addresses and their respective identities. Incoming mail is getting either sent to both, one , or the other accounts and seems random. Sending a mail to one address will ONLY show up in the other adresses inbox sometimes, and other times will show up in both inboxes. What is going on I have never seen this.
So there is no confusion, here is an example:
Two addresses, email@example.com and firstname.lastname@example.org
Say I send an email to email@example.com, it may show up in firstname.lastname@example.org and NOT email@example.com, or it may show up in both. It may even get lucky and show up in the correct one.