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In the Admin CP, Go to Apps >> Installed >> Contact
In the Contact App, you will find Categories. You can Add new Category or Edit existed menu here.
In the Settings section
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right
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before the Categories, you'd be able to see some settings as Enable Captcha, Allow HTML, and Staff Emails. 
You can also choose to enable your autoresponder message. set up the Subject and Message phrase.
After everything else's done, just make sure to click the SAVE CHANGES button and CLEAR CACHE for the settings to take effect.
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