what inboxes are included in the unified view that has over 500 though? You would not be using a unified view unless you had more than one account and hence more than one inbox.

Hello Matt, Thanks for taking the time to help me. I use Thunderbird to access my emails on my Computer,( that's where the over 500 number appears ) Outlook on my iPhone and Samsung email app on my Samsung Tablet. That is where the 540 emails were, on the Samsung email App which I had not opened or cleared for many months. Now that I know this happens I think I will keep things as they are as I have a real backup on my emails. Thanks for leading me in the right direction.