Two emails deleting only one selected

I click the delete button and the email in the preview window and the next one in the inbox gets deleted.  I tried using the delete button on the keyboard and the same problem occurs.  I am very careful not to double click or hold down the delete button but the problem remains.  I am not double clicking the delete icon.  Any suggestions.  WINDOWS 10 EM CLIENT 6.0.23421.0

Hi Ted,
that sounds like a curious issue, can I just ask about more about your situation? Have you tried restarting your computer? Did this just start to happen recently?
Is your Internet Explorer up to date? If so, can you try resetting it to the default settings?