I have an ASP.Net app. Username used to be 'email' but then not everyone wants to use their email address for usernames and not all employees offices that will be using the system have email addresses....
I have this for now, but what's a good username requirenment:
(Username should be minimum 6 and maximum 15 characters. Alphanumeric characters are allowed. special characters @._ are allowed. No spaces are acceptable. The starting character should be alphabet.)