Wi Fi connection problem WEP should be WPA2
I have a 2010 Mac Book OS X 10.9.5 . Recently I changed my Internet Supplier, got a new router (hub) and gave my Network connection a new name. But the computer will not connect automatically: I get a notice that "XXXX was previously joined as WEP and not WPA/WPA2 personal". Maybe I used that name once before, I don't remember. Anyway, it seems I can't delete it from my network list and I have tried setting this new one up as my first network in preferences but continue to get the message when I try to connect. How can I delete the WEP connection?
MacBook, Mac OS X (10.6.8)