I am trying to buy the latest version of PS. When I enter the serial number of my current (old) version of PS, the message I get is that the serial number is "invalid." I checked with customer support and they say I have the right serial # and that it is valid. Any idea what the problem is?
The latest version of PS is CC 2014.2. The CC Photography Plan is $9.99 USD/month and doesn't require any previous version. (At least I didn't need one and I jumped from Elements.) Once you buy the plan (on your Adobe ID), you just install the CC app and install PS that way; no serials required.