When does the undefined error show up?

You fill in the new account form on NTTGame's site, submit it, and the page just says "undefined"; no account is created. Players see it most around new server launches, on days when the site is very busy, and after several sign-up attempts from the same network.

How do you fix the undefined error?

There's no official fix; these are the steps players say work. None of them are risky:

  1. Clear the browser's cookies and cache, or try a private window.
  2. Try a different browser.
  3. Sign up over your phone's mobile data instead of Wi-Fi; many attempts from one network can get blocked.
  4. At busy moments such as a new server launch, try again a few hours later.
  5. If it persists, open a ticket on NTTGame's support site with a screenshot of the error.

How many accounts can one phone number hold?

After creating the account, ICS/OTP setup asks for a phone number. On May 13, 2026 NTTGame announced that one phone number can be used on up to 3 accounts in ICS, and changing a number counts toward that limit. Details in How to set up and activate OTP in Knight Online: ICS, AnyOTP, changing your phone and trade SMS.

Invalid email and username errors

If the form won't accept your email or username, check the spelling first: spaces, Turkish characters and special symbols can cause trouble. An email already used on another account may not work for a new one. NTTGame says password reset and security emails to Hotmail, Outlook and Live addresses can be delayed; check the junk folder.

Creating an account on the Steam version

The Steam version has no separate sign-up form; the game uses your Steam account. There, creating many accounts from the same PC in a short time can trigger the "Account Creation Abuse" block, covered in SteamKO account blocks.

FAQ

I can't create a Knight Online account. What do I do?
If you get "undefined", clear the browser and try another browser and mobile data. If a field isn't accepted, check the spelling; open a ticket if it persists.
Is the undefined error an IP ban?
NTTGame hasn't said. Players see it more after repeated attempts from one network; trying from another network or later usually works.
Can I create more than one account on the same PC?
Creating accounts is allowed, but one number can be used on at most 3 accounts in OTP/ICS, and joining events with several characters from the same IP is blocked.
The sign-up email never arrived. What now?
Check junk/spam. Hotmail, Outlook and Live can be delayed; wait a few hours and open a ticket if it still doesn't come.

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