Will automate the process of password protecting PDFs. PDF Secure is a high performance server tool from Traction Software for Windows PC, Unix Aix, Linux, Macintosh OSX, SUN Sparc Solaris, HP-UX
NOTE: This Software does NOT require Acrobat, PDF Secure is designed for server usage.

PDF Secure software automates the process of password protecting pdf's, encrypting pdf's, decrypting existing pdf's, re-encrypting, changing passwords, adding permissions & changing existing permissions in pdf's, can now add random passwords and create a list of passwords and create multiple copies of the output pdf with different passwords which is ideal for book distribution.
Includes Encrypt RC 40 bit and RC 128 bit support, Decrypts RC 40, RC 128 & AES

Parameters:
<input file> input file
<output file> output file
-d decrypt (default, auto detect encryption to decrypt)
-e40 encrypt at 40-bit RC4
-e128 encrypt at 128-bit RC4

-p<password> security password for opening document, use -p[RANDOM] for random password
-c<password> change permissions password, use -C[RANDOM] for random permissions password
-P<new password> change security password (for applying to new document)
-C<new password> change permissions password in new document
-modify modify current document permissions

-type=<string> Document restrictions p,p150,phi,cd,da,cc,cca,pe,c,fff,s,ctp
p = Printing (none)
p150 = Low resolution 150 allowed
phi = high resolution
cd = Changing the Document (none)
da = Document Assembly
cc = Content Copying
cca = Content Copying for Accessibility
pe = Page Extraction
c = Commenting
fff = Filling of form fields
s = Signing
ctp = Creation of Template Pages

-list create text list of files with password. e.g. -list mylist.txt or use .csv for csv file output
-copies<amount> create multiple copies of the same file, ideal use with [RANDOM] password

-log option, will output file log e.g. test-out.pdf.log
-nooutput option for processing if unlicensed or invalid license then it doesn't output an output file, dos return code -6 otherwise dos return -5

Limitations:
* Will randomly not process a pdf file, it will show a TRIAL message

The license of this software is Free Trial Software, the price is $249.95, you can free download and get a free trial.