Register as a developer, you can register at the following website. https://developers.facebook.com/async/registration+
Log in https://developers.facebook.com/+.
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Click 'MY Apps',
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Click 'Create APP',
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Select 'Business', click 'Next'
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Enter 'App Name' and 'Contact email', click 'Create app'.
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Page will switch to,
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Click Settings>Basic, Copy 'App ID' and 'App secret' here.
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Click Dashboard>Facebook Login for Business, click 'Set up'.
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Enter URL. URL is https://Domain:9001/api/v1.0/facebook/integration/callback. Domain is your Web Domain.
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Click 'Save changes'. And then click Dashboard>Messager, 'Set up'
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Click 'Add or Remove Pages' and continue.
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Click ‘Create a Page' and complete the page information.
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Click Messenger>Settings, 'Add or remove Pages'
Select a page, click 'Continue'.
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Click 'Continue'.
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Click Messager>Settings>Access Tokens, click 'Generate token'. And copy the token and paste it on the other file.
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Click Messager>Settings>Webhooks, Click 'Add Callback URL'.
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Enter Callback URL and token. URL is https://Domain:9001/fb/webhook, Domain is your Web Domain. Token is cloudfon-facebook.
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Click Messenger>Settings, click 'Add subscriptions'
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Select all, and click 'Save'.
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