I've never had to do this myself, but observing what vendors do, I'd say most use the registry, but some use a plain file.
Seems like with the registry method, the customer is "forced" to go back through your supplied installation procedure to move the app around in the filesystem, but with a file-based key, the customer can just move the thing with no hassle.

In reply to Re: [OT] Software registration and activation. by andyford
in thread [OT] Software registration and activation. by jdtoronto

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