can't merge separate PDFs into a single PDF

[Jeff_Kruthers@adobeforums.com]

I receive the following when attempting to merge separate pdf files into a single pdf file in Acrobat 8.1.2 using OS 10.5.4 on my iMac:
“At least one file in the list requires a password. The combined file will not be secured. Do you want to continue?”
I then get a message that a file in my list is “protected”, and I’m prompted to enter a “permissions password”. I don’t know what that is (the only password I have associated with Adobe doesn’t work) or where to locate it.
This problem has just cropped up recently, and currently I must send a list of PDFs instead of a single file.

[graffiti]

Did you create the PDF's? If not, it looks like someone has added security to it.

If you did, then you've inadvertently added security to one of them. You'll need to find out which one it is and remove the security.

[Jeff_Kruthers@adobeforums.com]

I created the PDFs, and I don't recall any step taken with regard to security (I've done all this before without any trouble). Where do I go to address security issues?

[graffiti]

I would work out which one is giving you the problem then recreate it and try again.

Not sure why it would say it had security if you've never added it.

[Jeff_Kruthers@adobeforums.com]

I've tried different combinations of different PDFs, and I always get the same message. Any idea on how to remove security?

[Mike Kazlow@adobeforums.com]

If the pdf is password protected, there any utilities available to
remove the password protection. Which explains why password protection
is not to be relied upon. If the protection is certificate based or
server based, then removing the security is a non-trivial matter.

....Mike

[Aandi_Inston@adobeforums.com]

You can readily check the security by using File > Properties; you
will see a security tab.

Aandi Inston