I purchased Photoshop CS4 a few years ago which allowed me to use the serial number on two computers, however the initial laptop I installed it on suffered fatal injuries and couldn't be recovered. The problem is that Photoshop is still technically installed on it, therefore the serial number can only be used once more.
I've since bought a new laptop, and PS is installed, but I'm wanting to install it (and use the serial number) on my work computer which the program will not let me do. Is it possible to cancel out the serial number used on that first broken laptop so that I can install it on my newest one?
Usually that kind of thing is possible, but since you no longer have access to the crashed system, it's not something you can do yourself... Only Adobe customer service can help since they control what's activated for your license in their database...
So your best bet is to contact them and see what they can do - for example resetting all activations of your serial number, so you then start over from scratch (and can reactivate as you desire).