5250 error 0008: Field requires alphabetic characters

What it means

Every input field on a 5250 screen has a keyboard shift attribute, set in position 35 of the DDS. Shift X means alphabetic only. IBM's DDS reference lists the characters an X field takes as the letters A to Z, the comma, the period, the hyphen and the space. Anything else is refused as you type it.

The display station does the check one key at a time. When you press a key that isn't on the list, it doesn't place the character. It locks the keyboard and shows 0008, with the cursor left at the position where the bad character would have gone. Everything you typed before that key stays in the field.

Lowercase letters are accepted. Unless the field also has CHECK(LC), they are sent to the program as uppercase. Digits, apostrophes, ampersands, slashes and other symbols are refused, and that catches people out when they type real names and addresses.

Common causes

• A digit typed in a name or code field, for example a house number in a street name field, or a code like UNIT4.
• An apostrophe in a name such as O'NEILL, or an ampersand in a company name such as SMITH & SONS.
• A slash, number sign or other symbol, for example in an address line like APT #2.
• The field is shorter than you think, and your typing ran into the next field, which happens to be alphabetic only. Check which field the cursor is in.

How to find the problem

1. Look at the cursor. It marks the place where the refused character would have gone, so the key you just pressed is the one the field rejected.
2. Press Help while 0008 is on the error line to see the system's text for the error.
3. In the display file source, check position 35 of the field's line. X means alphabetic only. A, the usual shift for text, takes any character.

How to fix it

• Press Reset (also called Error Reset) to free the keyboard. In many PC emulators Reset is the left Ctrl key by default. Then type the value using only letters, comma, period, hyphen and space. The characters you typed before the error are still in the field.
• If the value needs a digit or symbol, the field can't hold it as defined. Ask whether there is another field for it, or a different way to record it.
• For programmers, change position 35 from X to A if the field must take any text, then recreate the display file with CRTDSPF. Check whether the programs that use the file need recompiling to avoid a level check.
• For programmers, if you want letters only but need a better message, keep the field as A and check the value in the program, or with VALUES, and send a message that says what is wrong.

Technical reviewer: Albert Joseph, WND Software.

Last reviewed 2026-10-18 by the WND Software team. Written in our own words. For the full reference, check IBM’s 3270 or 5250 display documentation.