Not sure where to post this but recently on the desktop, when I do my email it shows I have one still left that 'isnt there' or if it is, I cant open it.

My email box inbox has no more than 20 in it that are ones I want/need to keep as I delete most I get every day otherwise.
The same with SPAM, once seen to ensure they are indeed SPAM, I delete those and then I go to the TRASH folder, recheck they are not wanted and Delete all thats there.
I do have a few folders with mail stored in them but I didnt want to create more for the few I leave in the Inbox.

I have a similar problem on my Wife's Galaxy TAB3 with the TRASH showing 3 still there after I delete everything.

Are these 'phantom' emails and I need either an exorcism or call an email buster to expel them ?