IKJ56700A: TSO prompt for a missing operand (ENTER USERID)

What it means

IKJ56700A is a prompt, not a failure. The A at the end of the message number stands for action. TSO has stopped and is waiting for you to type something.

TSO uses this one message number whenever a command is missing a required value and TSO is allowed to ask for it. The words after ENTER say what it wants, and the line ends with a dash. The version most people meet is IKJ56700A ENTER USERID -, which appears when a TSO logon starts without a user ID. You see it in line mode, on a mostly blank screen. Type your ID and press Enter. TSO then checks the ID and moves on to the password, usually on the full-screen logon panel where you can also set the logon procedure and region size.

The same message number shows up with other text. In a line-mode logon, as on older systems, the next prompt is often IKJ56700A ENTER PASSWORD FOR PAYU07. Type your password and press Enter. It doesn’t show as you type. The SUBMIT command, for example, can ask ENTER JOBNAME CHARACTER(S) - when it needs extra characters to complete a job name built from your user ID. Answer it the same way, with the value it names.

Messages ending in I, such as IKJ56420I, are informational. They report something but don't wait for you. A screen showing IKJ56700A won't go anywhere until you answer.

Common causes

• You typed TSO or LOGON on the welcome screen (often called the USS or VTAM screen) without a user ID after it.
• Your site's welcome screen sends you straight to TSO without asking for an ID first.
• An emulator macro or logon script sent the logon command, but the user ID part was empty or got lost.
• You entered LOGON from inside TSO with no user ID.
• You ran another TSO command, such as SUBMIT, that needed a value you didn't give it. The text after ENTER names that value.

How to find the problem

1. Read the last line on the screen. The words between ENTER and the dash tell you what TSO wants. ENTER USERID means it's waiting for your logon ID.
2. If you aren't sure what to type, enter a question mark. TSO can then show more detail about the value it's asking for, if your site has the help installed.
3. If a script or macro brought you here, open it and check the step that types the user ID. The ID may come from a setting that is empty on this PC.
4. If you answer the prompt and get another message straight away, read it. That message, not IKJ56700A, tells you what went wrong.

How to fix it

• At logon, type your TSO user ID and press Enter. TSO user IDs are one to seven characters. A longer ID is rejected with IKJ56710I INVALID USERID.
• You can also give the ID with the command next time, for example LOGON PAYU07, so the prompt doesn't appear.
• Don't type your password on the same line as the user ID, even though the LOGON command accepts it after a slash. In line mode the input isn't hidden, so the password shows on the screen.
• If IKJ56420I follows, the ID isn't set up for TSO on this system. Check the ID and the system, then contact the help desk.
• If IKJ56421I follows the password step, the password was wrong. If IKJ56425I follows, the ID is already logged on somewhere.
• For a prompt from another command, type the value it names and press Enter, or give that value on the command next time.
• If you write screen automation, wait for the ENTER prompt text before sending the ID. Typing too early can lose the keystrokes.

What it looks like

LOGON
IKJ56700A ENTER USERID -
PAYU07

Last reviewed 2026-10-12 by the WND Software team. Written in our own words. For the full reference, check IBM’s documentation for your z/OS, CICS or Db2 release.