I'm still getting the error.
I ran Norton update first (no new updates) and then re-downloaded the ZIP file.
Extracted Viewer 6.5 but before I could run it, Norton kicked in, flagged it and then deleted it. Error flagged as WS.Reputation.1 This is what Norton says about this:
Updated: February 15, 2012 3:15:47 PM
Risk Impact: High
Systems Affected: Windows 2000, Windows NT, Windows Server 2003, Windows Server 2008, Windows Vista, Windows XP
WS.Reputation.1 is a detection for files that have a low reputation score based on analyzing data from Symantec’s community of users and therefore are likely to be security risks. Detections of this type are based on Symantec’s reputation-based security technology. Because this detection is based on a reputation score, it does not represent a specific class of threat like adware or spyware, but instead applies to all threat categories.
The reputation-based system uses "the wisdom of crowds" (Symantec’s tens of millions of end users) connected to cloud-based intelligence to compute a reputation score for an application, and in the process identify malicious software in an entirely new way beyond traditional signatures and behavior-based detection techniques.
I have a screenshot of the error, but I can't see how to attach it to this post (don't have a URL for it)