Answered
Although links to a Windows Explorer folder view cannot be created with Acrobat's link tool, such very useful hyperlinks created in Office are successfully translated by pdfMaker.
In recent weeks these links have stopped working in v8 & 9, and throw up an erroneous message that the action has been disallowed by the system administrator.
The links still work in Acrobat 7 and earlier, so it looks like an issue from the turning on of 'enhanced security' update, but turning it off doesn't resolve the issue.
This has been reported by another user, so its not a local problem.
See related posts in the user-to-user forum:-
http://forums.adobe.com/message/3043714#3043714
http://forums.adobe.com/thread/306602?tstart=0
What you've encountered are new application security defaults that create white and black lists for application types that can be launched from an attachment, multimedia types, multimedia players, JavaScript APIs, and network and protocol access. You can find out more about these settings in the [url=http://learn.adobe.com/wiki/download/attachments/64389123/AcrobatApplicationSecurity.pdf?version=1]External Content Access Technical Guide[/url]. Check out section 5.1 on black lists and white lists.
To change the new black list behavior, you'll need to modify your registry as detailed in the documentation. The instructions also detail how you can propagate this setting across multiple machines using a BAT file during a user's logon or incorporate the changes in the Acrobat Customization Wizard for enterprise deployment.
Lori Kassuba is an AUC Expert and Community Manager for AcrobatUsers.com.