activate registration [CS3 is dead, locked]

I may be wrong on this, but depending on where you live consumer protection laws may require adobe to provide a way to activate your purchased software offline (since the online actvation is no longer feasible). This is probably the case in Europe (again, I may be wrong on this).

Sorry for the late reply.  What you ask is impossible.  CS1, CS2 and CS3 are dead & gone. The activation servers were removed from service years ago. Even if you find an installer, it's impossible to activate the software.

Time for new software to go with your new computer and operating systems 🙂

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