The version we used recently is Pre-release version, the serial number only valid till 31st Jan.2004
Activation is needed to upgraded into Full version:
There are 2 ways for D-version users to solve this problem:
First, download the full version from internet-TDA version(the file name is something like: photoshopcs_tda.exe). But I searched with google and baidu for a whole day, cannot find any link to download.
Second,the easiest way, what I am using:change your system date before 31st Jan.2004 whenever you install or use the photoshop CS.