If you are referring to WikiAnswers, it is more than likely that the username you tried to use does not exist here. You might have made a typographical error or you could have forgotten which username you use for WA. There is also the possibility that the username you chose was not acceptable and has been removed or changed.
If you are certain you should have an account under a particular name, you can always ask Answers Support to check into your problem. You do that through the Contact Us form under the Help Center.
Another answer:
They said it because they believe it to be true. Perhaps you forgot an uppercase, or used your full e-mail address, or forgot some numbers. They are not just messing with you, try to do a recovery, they will e-mail the proper user name to you.
Because, if you have never signed in before or make an account. Hope this answer helps!! Good luck ;)
When speaking you just say the username.
When you get a message that says a username does not exist, it means the username you typed is not stored in the website's system. You may have misspelled the username or made a typing error in some way. Make sure it is typed in exactly the way you typed it when you registered on the site.
it either means your typing in the username wrongm or your account has ben deleted,
You have to register and if they say username is not vaild you have to choose a vaild username.
Username : Esm al-mostakhdem ( in Arabic ). and it is written this way : اسم المستخدم
A Facebook Username is for your "special" page URL. Say if you used "Waffles" as your username (if it was available) your Facebook URL would be "www.facebook.com/Waffles", also, you can use your username in place of your email when you sign in.
Nombre de usuario
Yes, She Is Level 13, Judge, Celeb, VIP. Add Her ;)
no not at all. It will say re enter your username/password.
It should say before your username.
Your problem could be that you have not added extra lower or uppercase letters that are need or spacing