Thanks for the reply George.
So, using a DRM based approach would permanently prevent unauthorised viewing/printing? The encryption method is different to the way Acrobat encrypts a document? Could the file be passed through similar software to the above to remove permissions and/or password?
Still trying to get my head around this, sorry for all the questions!
That's the idea. The type of sotware you're referring to won't remove such security. The downside is the expense, but there are many cases where it's reasonable. It is a different security method that supports, and is totally different than standard password security.
Thanks again for this George. The features of ES3 look quite interesting but it's way more than we really need. Would be great if we could have the feature of advanced security without having to pay for features we will never use. I suppose this is usually the way with everything!
You can encrypt files for specific individuals using their public key and Signature-Based security. That just won't work for the general audience.
The thing is, this isn't just a problem with Acrobat. ANY password based security that allows for infinite tries can be broken on any file of any type. It's just math folks. The only way to "properly" secure a digital file is to separate the file and the encryption/decryption keys so that they don't travel together. That involves either a token or some for of network infrastructure or both. You just can't do it on the cheap.
That said. Take a look at FileOpen.com - they have some very affordable options.