This might relate to the matter - or not. It might be useful info for someone, in any case.
I tested a rip of the Japanese BD Ghost in the Shell 2. There are three directories: AACS, Certificate and BDMV.
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Note that during the entire exercise I didn't have AnyDVD HD running at all.
Now, I need to ask: what exactly were you doing?
You're saying, you tested a rip - this would mean, you copied and decrypted the original and tried to play it then?
Or did you simple copy the still encrypted files?
In any case: I think I recall, that PowerDVD uses the AACS directory as an indication whether the content is encrypted or not.
So it should never work at all to play a readily decrypted disc, unless you completely remove the - then useless - AACS folder. (this is why AnyDVD renames the AACS folder, to hide it).
Generally: in most cases, it is fully sufficient to copy the BDMV folder.
Only in rare cases (like pirates otc), you will additionally need the \CERTIFICATE folder, but I will remove the requirement for this folder with the next release of AnyDVD HD as well.
PowerDVD always shows this message, if it detects ANY problem with decrypting. In your case, it probably saw the AACS folder and then tried to authenticate with the drive - which is impossible of course.