Have you got 100s or 1000s of emails after upgrading to iOS 7 or 8? We show you how to fix the problem

After updating iOS, the Mail app might report that you have hundreds or thousands of unread emails. This is because it looks at your entire email account, rather than just the last few weeks or months.

It's a particular problem with Gmail accounts, especially if, like me, you don't delete your email and leave lots unread. You've scanned the subject lines, or the previews, but not bothered to open the messages nor trash them.

Well, here's how to mark all your Gmail emails as read.

Unread Gmail Apple iPhone Mail app

First, head to your Gmail account in a web browser. It's easiest on a laptop or PC, rather than your iPhone.

You need to select all your messages, and the way to do this is to click the downward pointing arrow in the search box and type gibberish into the 'Doesn't have' box. It MUST be a phrase that no email contains.

Clear unread Gmail - Step 2

Click the magnifying glass icon to search for messages and Gmail will find every single one of course.

However, only the first 20 conversations are selected, so click the link to select them all.

Clear unread Gmail - Step 3

Now, click the More button, and click 'Mark as read'.

Clear unread Gmail - Step 4

Gmail will warn you that this action will affect all conversations in the search. That's fine, so click OK.

Clear unread Gmail - Step 5

Next time you check for mail on your iPhone, you should see the number of unread mails has dropped to a much more manageable figure

Clear unread Gmail - iPhone fixed

Don't forget that the number is a total of unread emails across all email accounts you have set up in iOS, so if you're obsessed with making the number zero (and therefore disappear from the Mail icon altogether) be sure to read all your emails in other accounts too.

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