What has changed is Adobe's activation servers. So you must download it from their site and use the new serial number provided.
The activation server change should no effect you unless you installing CS2 and activating it. If your CS2 was activated and was running it should not stop running because of the server change. Something else must have changed. In any case you would need to use the new download and serial number fo fix your problem.
Hello Everyone who is having problems getting their Photoshop products to work. I had the same issues on both a Mac and a PC. Since Adobe seems to want to get customers to use their new setup online unfortunately they do not support the rest of us anymore.
Here is what I did for each:
MAC - Had to reinstall the whole program and it finally worked again.
The PC Issue was resolved immediately as well as the MAC