Server Administration > Item Fields > Creating Fields > Setting Field Editability > To define field editability in the GUI
  
To define field editability in the GUI
CLI EQUIVALENT 
im createfield or im editfield
1. From the Create Field or Edit Field dialog box, click the Editability tab. The Editability panel displays.
To prevent the field from being edited, enable Never Editable. This option is useful for fields that are updated by event triggers and are not meant to be edited by users. For example, you could create a date field where the date is automatically specified when the item enters a certain state. If you enable this option, proceed directly to the final step of this procedure.
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By default, this option is enabled for read-only custom fields (that is, phase, range, field value attribute (FVA), computed) and cannot be disabled.
2. Under Condition, define the conditions this field should be editable under. For more information, see “Defining Rules”.
3. Under Copy, do one of the following:
Click Add to copy editability rules from another field. The copied rules are appended to any existing rules.
If the field you are copying has a false editability rule (never editable), the rule does not appear. This means that a false editability rule cannot be copied.
Click Replace to copy editability rules from another field to replace any existing rules. The Rule Selection dialog box displays.
In the Objects with Rules list, select the field that you want to copy a rule from. If the field has a rule, that field displays in the Preview area.
Click OK. The rule displays in the Editability panel.
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If the field type is a phase, range, item backed picklist, query backed relationship, or computed field, a false rule automatically displays in the Editability panel. These field types display read-only values and cannot be edited.
4. Click OK to save the editability rule(s).