This wikiHow teaches you how to move an archived Gmail message back to your Inbox on an iPhone or iPad.
Steps
Method 1 of 2: Use the Mail Application of the iPhone or iPad
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Step 1. Open the Mail app
The icon is represented by a white envelope on a blue background and has the label "Mail". It is usually found at the bottom of the Home screen.
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Step 2. Click on Boxes
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Step 3. Select All Messages
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Step 4. Click on Edit
This option is located in the upper right corner. You may have to wait for a few seconds for this button to appear.
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Step 5. Select the message you want to remove from archive
Tap the circle next to the message you want to return to the Inbox. A blue check mark will appear to its left.
You can select multiple messages to transfer back to your Inbox by tapping the circle that appears next to each one
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Step 6. Click on Move
This option is located at the bottom of the screen.
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Step 7. Select Inbox
The selected message or messages will be transferred back to the main mail folder.
Method 2 of 2: Using the Gmail App
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Step 1. Open the Gmail app
The icon is represented by a white envelope with red borders. If you installed the app from the App Store, you should find it on one of the Home screens.
If you don't see your inbox, tap "Sign in", then enter the details associated with your Google account to continue
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Step 2. Press ☰
It is located in the upper left corner of the screen.
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Step 3. Select All Messages
You will need to scroll down slightly to find this option.
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Step 4. Tap the message you want to move
The content of the email will appear.
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Step 5. Press ⋯
It is located in the upper right corner of the screen.
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Step 6. Click on Move to Main
The selected message will then be moved to the inbox.