We have some external users whose accounts in AD are created with two user
names. In "Active Directory Users and Computers", they are called "User
Logon Name" and "User Logon Name (pre-Windows 2000)"; in an LDAP browser,
they are called "userPrincipalName" and "SAMAccountName".
The reason for the difference (as I understand it) is that we use email
addresses as account names for external users, and the "@" in an email is
invalid for the SAMAccountName. So at account creation, we generate a hash
for the domain part of the email. For example, the "userPrincipalName"
might be "joesmith@...", and the "SAMAccountName" might be
"joesmith!F324".
Right now, our SharePoint servers require such users to enter the
SAMAccountName to authenticate, rather than the userPrincipalName. (We are
using Basic Authentication with SSL, because many users are on computers
that are not bound to the domain.) Obviously, we would prefer that they be
able to use the friendlier "User Logon Name" (userPrincipalName).
What do we have to do to get there?