How can one turn off spell checking in Notepad++?

You can do this in one of four ways.

1. When installing; during the Choose components selection navigate to "Plugins" and uncheck the "Spell-checker" plugin.
2. In Notepad++ locate "Plugins" > "DSpellCheck" > "Auto-check document"
3. Alternatively for no 2, press the key combo Alt+A.
4. Press the toolbar button labeled DS or ABC (from version 6.5)

You can click the "DS" or the button (or Alt+A) to turn Spell-Check off/on easily:

The instructions are right on the download page:

If it does bother you, just uncheck Menu item Auto-check Document (Menu: Plugins -> DSpellCheck -> Auto-check Document).

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