How do I correct the spelling of a word flagged by the MPLAB X IDE spell checker?

On the word that is misspelled, highlight it and press Alt-Enter.
This will check the dictionary for various words and allow you to enter it in the project’s dictionary.

The dictionaries are located at:
C:\Program Files\Microchip\MPLABX\v3.00\mplab_ide\ide\modules\dict

You can add your own dictionaries, etc…
The private dictionary is placed in C:\Users\Administrator\AppData\Roaming\mplab_ide\dev

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