why am i unable to password protect a pdf file?

[micheles67122191]

I am trying to add a password to a pdf document.  I go to "Tools"..."Security"... and that's as far as I can go.

[try67 · Accepted solution]

Go to File - Properties - Security and select "Password Security" under "Security Method". Select your settings, enter your password, and you're done.

[Adrian24266446t7qj]

This method is not working for me. Neither is the previously successful way of password protecting a PDF doc that I've created myself. At the point where I either Save the doc or Exit & Save - the program renames the file using a number & character hash and tells me it cannot be saved to the folder I've placed it in. This behaviour began after a recent Windows 10 update and persists regardless of logout / login to my PC as well as my Adobe Pro account.

I'm stumped. Also more than mildly annoyed.

[Bernd Alheit]

Does you use a third-party plugin?

[Adrian24266446t7qj]

Hello Bernd, thank you for your reply.
I am not using a third party plugin . . . I am generating the PDF using my
copy of Adobe Pro as if it were a printer.
Thnx,
Ag

[Bernd Alheit]

How does you add a password? What version of Adobe Acrobat does you use?

[Adrian24266446t7qj]

Adobe Acrobat Pro DC - Continuous Release / Version 2022.001.20117
Added the password in two ways . . . using the method described in the blog
post.
Also - and usually - by using the Protect Icon in the side tray and
choosing Protect Using Password.
I've done this (literally) hundreds of times but it is NOT working as it
did before the most recent Windows Update(s).
Attempting a 'Repair Installation' from the Help tab after sending this
message.
Thank you for your time - appreciate the assistance.
Regards,
Ag

[Bernd Alheit]

>...  the program renames the file using a number & character hash  ...

I have never seen this.

[Test Screen Name]

One possibility is that you installed some security software that is blocking it. Especially ransomware protection.