May 08, 2014 06:40 AM|smirnov|LINK
If your user name in the Active Directory directory service contains one or more characters that have accents or other diacritical marks, you may find that you do not have to use the diacritical mark as
you type your user name to log on to Windows. You can log on by using the simple form of the character or characters.
Mehr dazu http://social.technet.microsoft.com/Forums/de-DE/79c40abd-efa7-41ce-af81-80145e74821e/distinguishedname-und-umlaute