Acrobat (Reader) 8 not capable of opening AES-256 protected rights management PDF?

[Former Community Member]

Is this really true?

Didn't find a datasheet explaining the Client-side requirements, when

AES-256-encrypting PDF documencs with LCRM.

In my lab it seems, as if Reader-9 can open those documents fine, while Reader-8 fails decrypting.

Dilettanto

[Former Community Member]

Dilettanto

Only Acrobat\Reader 9.x support the decryption of Rights Managed documents encrypted with a 256 bit key.

Regards

Steve

[Jonathan_Herbac · Accepted solution]

Acrobat/Reader 9 were the first version to incorporate AES-256 code, so if you want to remain backwards compatible with Reader 7 or 8 you need to continue to use AES-128. I believe this is documented in the help for the section that describes how policy edit works.

Jonathan