Download emails onto PC first before iPad

I have Windows Live Mail 2012 installed on my PC and my provider's email account on my iPad.  Up until recently my PC was the primary receiver.   If I opened new emails on my PC, they would not download onto my iPad as they had already been opened on my PC.  If I hadn't used my PC for a while, i.e. away from home for a period, all emails would download to the iPad but when I got home they would also be on the PC.  They would only download onto the iPad if they had not been accessed on the PC. Since I have upgraded to a new PC with Windows 10 and set up Windows Live Mail on it, all my emails download to both.  Neither is the primary receiver. I now have to delete the same emails twice!!   How do I make the PC the primary receiver, just like it used to be.