So I just upgraded to Yosemite. Obviously I have to re-sign into all of my Apple ID stuff. I sign into itunes, App store etc with the correct account and all seems good, takes the correct email and password, lets me into view my apple ID, edit, security etc. When I try to download updates from the app store though, it throws up a box asking me to log in again for each update (pic attached) but the email address in this box isn't my Apple ID email address, so it obviously won't take the password. I don't even know how the hell it's gotten hold of this other email address as I hardly use it for anything, and I can't see a way of entering my correct email over it. While this is going on I keep logging out and back in again with the correct email & password, but when I try again to updte my apps, it keeps throwing up this box with the unchangeable rogue email address. Driving me nuts. Little help? Thanks.