How to Make All Mail Unread Again in Gmail

Gmail allows you to easily mark all mail as read, but it doesn't offer an intuitive way to mark all of them unread again. That option does exist, but you will have to jump through a few hoops to use it. By default, when you choose to select all listed mail, Gmail only selects those on the current page. If you have more mail than can be displayed in a single screen, then the others remain unselected. However, Gmail presents the option to select them all, which allows you to change all of their attributes simultaneously.

Instructions

1. Log into your Gmail account.

2. Type "in:read" without the quotes in the top search field and press "Enter." This filters your emails to only those that are marked "read." Alternatively, type "in:read in:inbox" and press "Enter" to restrict the list to only read emails residing in your inbox.

3. Click the top-left check box immediately to the left of "Archive." This selects all the mail currently displayed in the first screen.

4. Click "Select All Conversations That Match This Search," which appears at the top of the mail list. This selects all search results.

5. Click the top "More Actions" button and select "Mark as Unread" to mark all "read" emails as "unread" again.