Valid characters in user names and computer names
Posted by Jim Bergman on
December 8, 2009
The Windows user name cannot contain these characters:
” / \ [ ] : | < > + = ; , ? * %
The Windows computer name cannot contain these characters:
{ | } ~ [ \ ] ^ ‘ : ; < = > ? @ ! ” # $ % ` ( ) + / . , *
The Internet standard computer name only contains these characters:
0-9, a-z, A-Z and – (hyphen)
Computer names also cannot be entirely consist of numbers, and should be 15 characters or fewer.
Wikipedia has a more in-depth technical explanation.