You might also find the new Actions Exchange at www.acrobatusers.com helpful-
Hope this helps,
Found my answer! http://answers.acrobatusers.com/ViewQuestion.aspx?questionid=16649
Basically, you have to change Acrobat's preferences (edit --> Preferences --> Action Wizard) to prompt for a password by default. That way, it can actually access the PDFs you're trying to work with.
Ye olde message:
So, I have the same goal (mass decrypt some PDFs), but a different problem.
If I have a step saved in the Action Wizard to "encrypt" the PDFs, with the security method set to "none." I have a bunch of PDFs with encryption on, but no password saved.
However, when I run the process, it doesn't actually remove the encryption.