To view the data in a password-protected drawing, you must first obtain and enter the password. After you enter the password, it stays with the drawing, even if you modify and save the drawing, unless you remove the password.
A password-protected drawing may contain external references (xrefs) to password-protected drawings. If you open a password-protected drawing that contains xrefs, you are prompted to enter the password for the current drawing. Then you are prompted to enter the passwords of any xrefs whose passwords are different from a password you have entered in the current session. A specific password that applies to a drawing or xref generally is required to be entered once per session.
If data in a password-protected drawing is read for any reason by the program, the password must be entered at least once per session of program use.
A drawing and its external references remain password-protected until the passwords are removed. You generally should remove passwords before performing batch operations on files, unless you are signing files.
To view data in a password-protected drawing, you open the drawing in a standard way and enter the password. Passwords are not case-sensitive.
You can view drawings that contain xrefs to password-protected drawings.
You can view drawing properties, such as the title, author, subject, and keywords, unless they were encrypted when a password was attached to the drawing.