Beyond photoshop CS 4

[marks7128949]

I am a current user of cs4. Liked it a lot but wish to place on another computer but cannot because outdated serial number. What should I replace cs4 with? I use layers and extract tool for my editing. What Adobe program would be most similar to Cs 4? Should I consider just purchasing another cs4 off EBAY? TIA for the information 

[JJMack · Accepted solution]

Your CS4 serial should not expire its a perpetual licence number.  However, CS4 is somewhat outdated its old,  has no support and lack Photoshop's new features.  Adobe no longer markets perpetual licences for Photoshop.  A related  Adobe product  you can be purchased a perpetual license for would be Photoshop Elements. Elements is some what a subset some of Photoshop features, tools and support not all. Support and features advanced Photoshop user use are not included.  However, some novice hand holding  features have been added to Photoshop Elements.  So you can use Element using a UI  suite for a novice  user or use it with a UI that is quite like Photoshop's UI minus some features and support.