Why does my iPhone 4s notify me when an email is deleted on my PC? When I delete an email on my PC my iPhone notifies me of a new email. I have looked for a setting to stop this.  Does anyone know of a way to stop this?
It sounds like you may be using POP instead of IMAP as the email protocol.  Look for directions on how to setup IMAP from your email provider for your iPhone and PC.  

Example: Gmail.