Whats the best way to upgrade from 8.1 Home OEM to 8.1 Pro Retail..

Would I have to reinstall ? I dont want to buy a upgrade Pro key when I have a new Retail key.
Could I use a ISO burnt to a USB stick to use as a upgrade ?

Whats the best procedure for doing this without losing files etc..

You should be able to "Add Features to Windows", with just the product key from your Retail Pro purchase?
(choose: I already have a product key)

http://windows.microsoft.com/en-au/windows-8/add-features-frequently-asked-questio

You should be able to "Add Features to Windows", with just the product key from your Retail Pro purchase?
(choose: I already have a product key)

http://windows.microsoft.com/en-au/windows-8/add-features-frequently-asked-questio

Tried that, just keep getting an error "Something went wrong" no other information was given...

Tried that, just keep getting an error "Something went wrong" no other information was given...

Were you connected t the internet during this attempt? (Internet connection is requ