Can I play Blu-ray discs if I declined to update PowerDVD when prompted?

No, you may not be able to watch Blu-ray Discs if you declined to update PowerDVD. PowerDVD needs to update because the AACS key requires periodical updates for content protection reasons. Blu-ray Discs have adopted AACS (Advanced Access Content System) to protect the digital content. AACS keys are required to play some Blu-ray Discs titles.