After uninstall... In XP & Vista was able to activate after deleting all Roxio, Sonic, Sonic Solutions, & Macrovision related keys/values -- i.e. search in Regedit for Roxio & Sonic & delete keys that only effected Roxio & Sonic, delete values when the key refers to other software as well.
Notes:
Deleting just Roxio & Sonic keys under HKCU\Software & HKLM\Software was useless.
Knowledgebase & other sources advise backing up registry by exporting entire registry... Personal experience suggests that this is useless -- merging the .reg file storing the entire registry didn't/doesn't work, AND, merging a .reg file DOES NOT delete keys/values, so if you added something wrong, it's still there and wrong! Alternatively setting a restore point does back up the registry, & if/when restored, should remove added keys/values. HOWEVER, please be aware that if you dual boot with Vista, Vista restore points can be deleted when you boot into another OS like XP.
Problem (in my opinion) seems to be Macrovision, which (also in my opinion) has a history of screwing up the implementation of their copy protection. In Vista notice to activate mpg2 can occur long after working install. Roxio EMC9 software may refuse to start after disconnecting network, suggesting monitoring of system. Regardless the method of disconnecting network to force manual activation dialog seems moot -- activation fails without actually attempting network access in my experience. Obviously efforts to turn off firewalls etc will not help in that situation.
