I'm having a similar problem. I'm running 4.3.4 and my PDF files open up in a new window but the page I originally clicked from turns blank. I have to close the new window with the PDF and THEN click the back button on the blank page to see the page I was viewing when I clicked. If that made sense.

And on some browser/Adobe combinations Acrobat opens like it's going to display the file but never actually does. If I hard code a fully URL directly to the pdf it works fine. But if I select the file through the HTML editor it does not work. It seems to be going through the linkClick.aspx file...which isn't even included in the 4.3.4 release. Ive heard this setup has changed with a recent release.

Help: I can't open PDF links with DN!!!!

We are having the same problem on a platform that we host many dozens of clients on.

PDF files that our clients uploaded and linked to prior to the 3.3.4 upgrade work fine and have a different link structure.  PDF's inserted after the upgrade do not open properly in IE - although they appear to still work in Firefox.

please visit this page for an example: http://www.pilgrimucc-durham.org/PastorsMessages/tabid/4249/Default.aspx

The first five pdf links at the bottom of that page (July 2nd - July 30th) were all put in when we were using 3.2.2 and have a link structure that looks like: http://3077.webmedley2.com/Portals/220/Sermons/0709sermon.pdf

The last three pdf links on the bottom of the page (August 13th - August 20th) were inserted after upgrading to 3.3.4 and the link structure looks like: http://www.pilgrimucc-durham.org/LinkClick.aspx?link=Sermons%2f082006.pdf&tabid=4249

When clicking on any of the 3.3.4 generated links in IE (I tested this with IE version 6) - you get whisked away to a blank page and it appears that the pdf will load, but it never does.  Firefox seems to load it fine.

This thread seems to imply that this problem is somehow the fault of Microsoft or Adobe, however, given how differently the linking system seems to work in DNN 3.3.4 and the fact that they worked fine in 3.2.2 and now don't in 3.3.4 and the version of my browser and Adobe software hasn't changed - it would lead me to believe otherwise.

We have dozens and dozens of clients affected by this change who are very displeased with the sudden inability to effectively use .pdf documents on their sites.