Introduction
This article provides a step-by-step guide to removing a configured Exchange account from the Android Gmail App.
Method
Open Gmail App
Click on the menu option in the top left – this is three stacked horizontal lines.
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Tap on Manage accounts
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Tap on Exchange mailbox (this will be identified by the text Exchange underneath the email address)
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You will be shown a screen titled Sync. In the top right of the screen, tap on the 3 vertical dots (under the time in the screenshot below) and then tap on Remove Account.
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The app will prompt you to confirm removal. Tap on Remove account.
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The app will now remove the Exchange mailbox. If the account was fairly large, your device may be slow for a little while as the mail data is deleted.