Unregistered users can view image attachment but cannot download pdfs

[spk100]

Hi,
I have a few sub forums where users upload pdf and image files.
Now, i want my unregistered users to view the images but if they click on the PDF i want them to be taken to the login page where they can login or register.

I am unable to find this option. I see either allow or disallow viewing attachments.

 

[Paul B]

That would require custom development - all attachments are handled the same.