title: Google Doc Viewer sometimes requesting login
body: <p>I am using Google Doc Viewer to display local PDFs on our site (override for IE7 and 8 because of permissions issue): <a href="http://www.scad.edu/news/index.cfm?pageid=338423" rel="nofollow">http://www.scad.edu/news/index.cfm?pageid=338423</a>. The issue is that sometimes people have experienced the PDF not being displayed, being replaced with an iframed Google sign in page. I am having a lot of difficulty reproducing these results, trying several browsers, even clearing my entire browser cache, using off-site browsers such as Adobe BrowserLabs and BrowserShots, etc. I know the error is occurring on an OS X 10.5 machine running Firefox 3.5.2 and on another machine with similar software. The not-so-technical personnel are claiming it happens after not having signed into Google for a week or so, but it displays fine for me when I am signed out on a fresh install. And yes, I have witnessed the issue several times on their machines but simply can not reproduce it.</p>
  
  <p>Please advise on how to hunt down this bug. I can't find anyone else with the same issue. I am considering just switching to Scribd PDF viewer.</p>