I think I'll have a look at the TuneEdit executible to see if i can learn how the software validates an approved license code... purely as an educational exercise, mind you..... now, grabbing my IDA Pro, Ollydbg, and favorite hex editor...
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Okay, it looks like the license keys sent by tuneboy are stored in a registry key. TuneEdit checks these registry keys for a vaild license key. It looks like there are only about a dozen sub-functions that touch the registry key where the valid licenses are stored. It's now a matter of finding which of those dozen functions loads those values into memory and does a compare (for validation).... stay tuned, so to speak.
something like this:
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