If you receive this error "Email is unavailable" when trying to send or view emails on the IOS mobile app, you will need to configure the default mail app on your device. You can configure the default mail app and prevent this error message by following these steps:
- Launch Settings from your Home screen.
- Tap Mail, Contacts, Calendars.
- Scroll down and tap Default Account.
- Tap the account you would like to use as your default mail account.
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