Undefined namespace

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

PhpUndefinedNamespaceInspection

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | PHP | Undefined symbols

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection PhpUndefinedNamespaceInspection

note

Actual comment syntax will depend on the code language you are working with

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

• IntelliJ IDEA 2025.2

• PhpStorm 2025.2