Hi folks, I am trying to help a friend with an old Macbook Air upgrade to 10.10 - the minimum OS he needs in order to run a particular program. His MBA is currently on 10.6.8. The system requirements to install Sierra are a bit much for his MBA, so he just wants the minimum level OS required to run the software. Is there any way for him to only upgrade to 10.10 at this point? Hope so! Sorry if I am posting in the wrong forum and thanks for any help in advance!