The primary goal of GuaPDF is to - remove restrictions on any PDF document (you should have the right to do it, for example, if you forgot the password). Any Acrobat version up to 9 is supported, even with 256-bit AES or 128-bit RC4 encryption. PDF permission password removal is an instant process. Decrypted file can be opened in any PDF viewer without any restrictions so you may edit/copy/print it. GuaPDF can be also used for - remove the PDF open password. Decryption of the file with password for opening is guaranteed for PDF files with 40-bit key only (Acrobat 3, 4 compatible encryption). This process takes several days on one home computer.