However, when I try to install them, I get the following message: 'The serial number you entered is not valid. I just purchased a new MacBook Air and would like to at least install Acrobat 9 on my new computer internal HD, and preferably install the entire CS 4 on an external HD (b/c there is not enough storage space on my MacBook Air internal HD). I purchased Adobe Creative Suite 4 Design Premium for Mac OS (disc installation version) back in 2009 and have had it installed on the same MacBook Pro for the last 8 years.
